There's a lot to choose from and over the past 36 months or so as shortages have come and gone, I took a risk or two and things paid off.
So, when I bought my first keg of Nitro 100 it came in an 8 lb jug labelled "not for use in handgun loads". Well, that's what I bought if for, and so that's what I loaded. Since then, Nitro 100 'New Formulation' has shown up is published handgun loads in increasing numbers, and amazingly, many of those loads are very close to the ones I put together. In .40SW and .45ACP, especially light charges with heavy slugs, it can be consistent and accurate. It's a great choice for IDPA loads and USPSA super-wimp loads. Shoots real nice.
Solo 1000 for similar loads in 40SW and 45ACP, and of course Clays--even better. We're talking 3.2-4.0 gr charges in both calibers and 180-200 gr bullets. You can definitely come up with some fun shooting action loads with those propellants.
For more serious 45ACP sd loads, I've taking a real liking to 4756. A few folks have said they're not so impressed, but I find that this powder, maxed out with Hornady XTPs, is a smooth-shooting, accurate, low-flash powder that's the one I choose for carry. Universal might be nice too, but I found it has to be loaded heavy or not at all, and it seems to produce a harsher bite on recoil and blast.
Right now, I think I'm in love with Power Pro 300-MP (Alliant) for my big boy 45 Magnum loads. It looks like its going to produce all the accuracy I'm capable of, but maybe with a bit nicer 'feel' in the upper end over 4227. In 45 Mag and 44 Mag I have had no experience with H110 since it just hasn't been on the shelves, but 4227 and 300-MP seem to do all I need them to do, since I'm not a hunter and punching paper, even with manly loads, affords more options I think. I dunno.
HS-6, HP-39, Titegroup, WSF or WST, and a few others have been nice to have in quantity to load ammo in quantity. Very seldom do I accidentally stumble onto a load that says 'wow'. 4756, Clays and Nitro 100 have done that in the 40SW and 45Auto. In 10mm I am just about to load No 9, and I have every reason to believe that will be The One in that caliber. 800X is off my list forever for any reason, any caliber. Longshot I have 8 lbs of because I could, and because I got the message 'try it again'...after struggling with it everywhere. Loud, blasty, and high recoil--destroying my 10mm brass even in moderate loads--I will try it again because smarter people tell me it's wonderful.
Gotta keep those options open in these tough days.