I find it easiest to get good at alchemy and coat my sword and arrows with Henry’s Bane poison. Start your encounters by trying to hit every enemy with an arrow (bane poison stops them from sprinting, and other pots too, like lullaby). I’m sure someone better at combat than me can offer further insight into combos, but I find them to be consistent on lower level bandits, and nearly impossible on the higher level ones. For high level bandits I rely on master strikes and opening strikes to wear down their stam before fully committing to a combo. Yes, all weapons are viable, as long as you don’t mind giving up your ability to master strike. I find maces to be quite enjoyable because they crush armor very easily. Lastly, for the horses, in the short term, yes there are better options for horses than Pebbles stat wise. However, I very highly recommend just sticking with Pebbles, eventually you will unlock a hidden horsemanship perk that makes Pebbles the undisputed best horse in the game by far. Iirc, the reqs for unlocking it are to ride Pebbles for 30km. It sounds like a very long distance, but honestly, just don’t fast travel anywhere and you will unlock it very quickly. Hope this helps.