However there is one area where I play with a slight tweak to Aaron. Not to make him harder but to aid my poor memory. In solo the 6 turns in each round get squashed together as you are the only player. I get confused when I'm paying 3 silver to take an extra action, as it can be played only once per turn - which can get confusing at the end of the round. So having a mechanism to separate the turns is useful - I do it by not turning over all of Aaron's cards at the start of the round, but one at a time. He gets his first card at the start and then another one after each of my turns (until he runs out). This helps me separate my turns but also adds some tension as I don't know what he will get next - and I can race him to be the first to complete a particular triple.
Interesting idea! While I haven't had trouble keeping turns under control (but I have caught myself picking up all 6 cards and looking at them, then realizing it's only two at a time!) your idea does give a nice variation to Aaron getting the leftovers. And does give the player some hope they can get a triple or one of each kind before Aaron...
And just for my own memory, I wrote how many cards Aaron gets at the top of the Round cards....