revising before finishing the first draft?

If it were me, I'd go back and fix it. But I edit as I go anyway, so that's just the way I write. If it's such a big change, though, that it is going to alter all of the interactions they've had, you might as well go back and get it right before moving on, IMO.

Yes, go back and fix it. If it's something that will effect the rest of your plot, fix it now.

I got a third of the way in on my current project and realized I started my story at the wrong point in my MC's life. It was throwing off her entire personality. I had no choice but to two rewrite the offending chapters and go back through and edit the entire thing. I only lost two weeks and my story is SO much better for it. Some things you can skip and fix later, but major things, like characterization will be much more work if you wait until you're finished.

I love male POVs!

As for tricks...there's reading books with male POVs, basing your MC off a guy you know in real life, and going out with a notebook and pen and watching people.

I have a brother, so I'm sure being around him and his friends gave me a disturbing amount of insight. I also had an uncle that hung around all the time a cousin who stayed with my family all through his college career. Look at the men in your life. Watch how they act. Studying people can be a lot of fun and makes for a great writing exercise.

Some guys are over analyzing door mats though...

I'll second the advice to read lots of books with male POVs. Don't just read them from a reader's perspective, though. Analyze how much time is spent on dialogue, pure action, internal thoughts, etc. Then break down those internal thoughts to see how much time is spent with problem-solving, angst, hormone-induced observations, etc.

Personally, I find it easier now to write male POVs than I do female. Weird, I know.

Happens all the time. I'm 95 pages in and I realized the location for the book had to change. Personally, I revise constantly up to the point of submission. So go with your gut and fix it now.

Also- you could have your male character have a 'man up' moment where he tells the heroine to stop being such a dumbass, but in manly terms. Think John Wayne telling Maureen O'Hara how it was going to be in 'The Quiet Man'.--If you haven't seen that movie, even though it's a ye olde, please do. It is awesome.

Congratulations on writing 180 pages of rough draft.
Yeah!!

As to major plot changes:

You can go back and fix it now,
or
you can go back and put brackets at the beginning of the various scenes that say
[Henry slugs him.]
or
[Add more forceful language for Henry.]
and keep writing ahead as if you have already made the changes
and do the changes in the brackets in the second draft.

There are proponents of each method.
I like to plow ahead to the end of Draft One, then go back and fix stuff.

You should choose the technique that works for you. You may not know which is right till the fifth or sixth manuscript.

Personally, I would go back and fix it now. Mainly because waiting and then going back may change how the whole story goes, so you'd end up re-writing a lot more. I'm not a fan of continuing as if the changes were made, because until you actually make the changes... kinda like buying carpet to go with the paint sample.

I usually say make a note of what's to change and continue. But in this case because it's characterisation, I'm going agree with changing it now and then finishing. You've written 180 pages with him characterised one way. If you continue then even thinking you want to write him a different way then your brain is going to tend to resist that, because it thinks it already knows this guy and will tend to get back into the familiar groove.

So I'd go back, do some rewriting. Keep it fairly rough, you don't have to do a complete polish of the thing at this point. But make the changes that change his characterisation and as you go through that should hopefully reset his character in your mind. So by the time you get back to the point you stopped you've got this new version of him fixed in your head and can continue with his new characterisation.

I make changes as I write. I juggle so much of the story already, that I may think I've fixed the issue when I have only thought about fixing it. That always bites me later. So I've learned to edit as I go, or at least make notes.

I'm in agreement with "fix it now" for several reasons, most of which have been mentioned above. But I'll add another thought, or perhaps just expand a bit.

The story as written so far is in your head as you're writing. You remember each line and every scene. The interactions, the emotions, etc. And this is all held in the forefront of your mind as you continue to create your story. For me, it would be impossible to continue on, pretending that I'd already gone back and changed whatever I decided to change. My writing from that point would suffer. My thoughts would be in a jumble.

Example: I just finished the "true" first draft of my latest project last week. I say "true first draft" because I finally wrote the last line - all 356 pages and 97,979 words! But in reality, with the exception of those last few chapters, the rest of the book had already gone through three full revisions. In one of those revisions I had gone back to the beginning after writing a good one third of the book because I decided to completely change the personality and purpose of one particular character AND to move a certain scene far earlier in the story. In other words, a major rewrite. My next revision involved bringing in a new character. I could not have moved forward if I hadn't stopped and gone back to make these changes.

My third revision came because I hit a wall when I reached the wrap up stage. I knew where I wanted to go, but wasn't exactly sure how I wanted to get there. (some of you might call that writer's block) When I get in that position, I go back to page one and read it all again. Revising and editing as I go, of course, but because that usually helps me to visualize what's next. And I've been productive at the same time.

This is one of those "it all depends" kind of things. I know writers who insist that you should just plow ahead and get the first draft finished before you go back and revise. Me, I can't work that way. There are some things where I can just insert a note to myself to add something or beef up the emotion in a scene, but there are others where I have to rewrite it because what happens then affects everything that follows.
But that's me. You are the only one who can know the best way for you to work.

I'm a little late to the party, but, and this is just me, I'd start all over. Seriously. What you want to change will effect the entire story and I never could just pick and chose. I always end up having to sacrifice the things I like about the story when I have to make major changes. But if the pick and chose methods works, go for it.

If something needs to change, I change it. I revise and edit as I write so that my first draft only needs minor revisions and cleanup.

As for writing guys, for me it's like writing any character. I get to know him, then his actions will all be in-character and perfectly natural. I think of it almost like an actor getting in character.

Also... Ann, I love The Quiet Man. Maureen O'Hara is the perfect bratty sub, just waiting for her man to Dom up.

It might be a bit late for advice but I wanted to reply because until recently, I have been a "revise as I go" writer. The problem was I wasn't finishing anything I started. I started a new manuscript resolved that no matter what happened, I would plow through to the end. I am now at 30,000 words and so far, so good. I've had lots of ideas about changes, and when I have them I type them in red. Once I finish my first draft I will allow myself to go back and amend.