Never ending saga

Ok..Thanks to 2MANYZs and Carguyinok I have a better understanding of what I have already and what is possible.. Having said that I think I'm ready to ask intelligent questions...

I have a 74 260 N42 block bored .020(I think)w/Turbo flywheel, SU carbs, E88 intake, N42 head, dished pistons.

I would like to raise the compression to about 10:1(I'm told anything higher requires special gasoline ) and reach Hp/Torque levels of about 200. I am looking to keep this a daily driver with good response from about 2500-6000 rpm. I'm not trying to make a racer,yet, but just a good off-the-line arse-spanker:devious:

Now..I've been advised be some to seek a P90 head and flat-top pistons rather than the N42.Will flat-tops raise or lower the compression of P90s(I've heard both)? What of oversized pistons .020/.040 are they necessary or even helpful? Any special work required to make them fit? I've seen some nice ones at MSA..Finally I'm looking to upgrade or get my cam re-grinded(is that even possible?) At any rate any suggestions on cam grinds..@MSA 260 duration .460 lift, 274 .480, 270/280 .460, or 209 .495 ? Whew..I nkow this is a lot but it all seemed connected somehow..Plerase help..

Thanks in advance...