Hi Jannkuzel - as far as duplicate content, it depends on what pages are being tagged as duplicate content as far as what you do to correct. For instance, the tools in SEOmoz tell me I have dup content for about 50-60 pages on one of my client's sites, but the reason is because each of the URL's is the same except for a product ID (&pid=540985). Each id loads slightly different content into a few areas of the page. So, the system thinks these are all the same page. These pages are not important pages on the site so I'm not that worried about them. Without knowing what is on your pages that are being tagged as duplicate content, it's hard to tell you what to do to correct it. Generally, you are on the right track in that you want to change the content on each page to be different enough (keep in mind that the info that is spiderable needs to be unique, pics, iframes, etc don't make much of a difference) that it won't get tagged as duplicate content.

As the title tag is the most important on-page ranking factor, you want your targeted keyword to be at the very beginning of the tag, with as close to an exact match of the keyword as possible. Even though it's a pain, yes, you would want to give each of your 200 pages unique title tags. It's fine to put the Brand name at the end, that's normally where I put mine.

H1 - is actually not quite as important as it used to be, but is still very important. H1 doesn't really have any relation to the Title Tag. Bottom line is that again, you want as close to an exact match of your main targeted keyword(s) in the H1 for sure. Also helps to work them into your other header tags as well (h2,3,4). Find a balance between making it legible and working in your most important targeted terms. If at all possible, use the exact term you are trying to target. Positioning (beginning or end of tag) doesn't matter as much as it does in the Title Tag.

Let me know if this helps!