Gal to Peasant ratio?
I was playing with the Gals I could rescue and using Peasants for the rest of the crew. I also only had 10 Loknar which I used for the cave/underground missions.
There is no "golden" ratio. It depends on your transport craft, your choosen path, your playstyle and stuff like that. If you rely on Peasants then you should only use gals as melee warriors and heavy weapon carriers and maybe as a shock troop, or two, so at least x3.
I don't know if you are far enough to know about "paths", because there will be a research where you can decide to go full on Peasant Revolution, focus on Gals, or go with a male touch.
Best early pistol?
I've enjoyed the Confederate Eagle and the Handcannon but they are heavy for Peasants. Best Peasant handgun?
That would probably be blackmarsh pistol, later shiny niner. But the beauty of this game that there is so many handguns that you can decide what works best for you and your playstyle. For a inexperienced megamod players, which I assume you are, blackmarsh pistol seems like the best choice, fairly big mag, low TU to shoot, decent accuracy, fairly light.
Best early SMG/Rifle?
My peasants are usually too weak to carry a decent shotgun in the early game so I stick them with an SMG or a Rifle. Assault SMG might be my favorite. Linux SMG for the Gals or the peasants that can carry it.
UAC carbine if you can get your hands on it, fairly good "sniping" SMG, but only if it is a decently trained peasant. Otherwise it should be a shotgun, for me I usually run coach gun as a main peasant weaponry. Longer effective range than most shotguns, ability to load phoenix shells, inbuilt melee.
Best early Throwable bomb?
I only embraced the Black Powder Bomb a few playthroughs in but I really like it now on almost everyone who can fit one on their loadout. Better grenade choices?
Black Powder Bomb is like the only available thrown explosive early game, so there isn't much choice to make. Molotov I would say is a different category, being a thrown incendiary, serving a different purpose than BPB. Next in line are HE and frag nades looted from enemies and stick nades if you get humanist soldier captive and a bit of research.