Does it work? Are there any "tweaks" I can do to improve the idea?
I've never done a 2hander on horse, so can't comment on the effectiveness of that, but here's a suggestion:
You could create an instant level 30 skip the fun alt with those stats, either skip the 1 shield point or take 1 from athletics because you'll be riding most of the time. Wear peasant clothes and use a practice longsword until you have enough gold saved up to buy a rouncey and medium cost armor and weapons. See if you like it, then go back and start leveling up your main character and maybe delete the STF after a week and make a new one to experiment with however you want to tweak the stats.