Yeah, I recommend trying the micarta up to 800 grit or so, and feeling it for yourself. I think you'll find it's still very grippy. Worst case, you can always step back down to a courser grit if you don't like it. I understand what you're going for, but I think you'll find you're over complicating it.
I know some guys sand blast micarta or g10 to get higher grip, but most of those guys use screws/bolts/etc afaik.
On the other hand, this is another area where domed pins excel, not only do they give a better mechanical fastening (especially in peel, which is where adhesives usually have significantly lower strength than sheer, and subsequently fail), but they also allow you to finish them separately, however you want. After peening the pin, you simply punch a hole the size of your pin in some blue painters tape, put the tape over the handle leaving the pin exposed through the hole, tape up the surrounding areas, and then buff in every direction. Depending on the material, use different compound or buffs, but a sisal or reinforced cotton buff with green chrome will handle most harder metals. For silver and other precious metals you can usually just use white rogue and a loose buff. Takes about 10 seconds and you've got beautiful, strong, independently polished pins. If you don't like them buffed, you can then rub them with grey scotch brite or 0000 steel wool to give a matte finish.
As far as ground flush pins finishing separately, I can think of a couple of pain in the butt ways to do it, but they'll be difficult to get consistency and not leave a ring around them in the handle material. As Andrew mentioned, using a cratex wheel is likely the best bet.
If you wanted to use flush ground pins and blast the handle material for a really grippy finish, I'd finish the handle, mask the pins (with a small dot) fittings, everything, with electrical tape. It'll resist a brief, direct attach by course grit blasting media, but it's a big pain to get everything sealed up correctly. If you dont, trust me, the media will scratch up everything and mess up all sorts of things. If you're pinned together, the last thing you want is to get a piece of blasting grit in the action of a slipjoint.
FWIW, here's a photo of a knife i made using this technique, except I blasted the fittings, not the handle material to give it texture and grip. I think it's pretty cool, but it took a lot of time to get it all setup properly, as blasting was the second to last thing after the knife was pinned together and finished, except for anodizing the titanium:
