My advice would be to the contrary... don't worry too much about what tartan you wear, as "named tartans" are relative newcomers to the world of Highland dress. The Scots have been weaving tartan for 2000 years, but they haven't been naming those tartans for even 1/10th that time.

...that said, tartans do mean something in today's world, and it's important to take that into account too. At any rate, just be aware of any associations that a tartan you're wearing has.

That said, wear what you like and what looks good!