Texture and color question

Ok I've been scanning the board off and on for months LOL.  At the moment I'm not ready to make the monetary investment for the extensions (my hair is shoulder length already, I'd like a bit more length but mostly for volume when not curled as I'm fine and stick straight--enough so that my ears show by the end of the day if I don't fluff it up).    I can't decide between microrings or protac yet (I don't want things to show which I fear for the microrings but something about tape doesn't seem so good either LOL)  It seems to be that for hair most people feel that Bohyme is the way to go but I'm not sure of color and texture..So here is my current 2 main questions:

1) I do have very straight fine hair.  It takes and holds curl relatively well but I'm living in a very humid place now and when it rains, forget about it.  I also have 2 young children and don't always have the time to curl, etc like I'd like so at the moment its ponytail, french twist, ponytail, french...you get the idea.  Anyway, if I go with something like natural body or french wave, does the difference blend in with straight hair to make sort of a middle ground or does it just look awful and obviously 'different'

2) I currently color my hair with goldwell topchic a 50/50 blend of tourmaline and light copper gold.  I can't tell from the colors which is the closest to that.  I have natural dark blonde hair that to me looks black though hairdressers always tell me its not LOL  I use a 20 vol peroxide with the above if that gives you a clue the result is redder than my natural color but very natural for my coloring it does fade in the sunlight (I'm in the Caribbean now so that is very noticeable)...given those things, which color would anyone suggest?  I don't really want to get anything too light because my complexion is so light that it starts to match and not be as flattering...

Ok, I've rambled on and on so I should shut up now.  But before I go, thanks to everyone who posts and I LOVE all the pics and demos.  Maybe one of these days I'll feel good enough to jump in the pool too!  If I could just figure out if I want to go with rings or protac ....