In regards to Han's actor problem, I see the problem similar to whenever a new 007 or a The Doctor is cast. You will deal with the backlash, but all that matters is when you stop thinking of what could be, and just watching the film or television show.
Could there of been better actors then Alden? Oh definitely, and if anything, I would've taken up someone else, but that I am not going to be completely pessimistic over just a few seconds of dialogue exchange that probably doesn't mean much, as more reshoots are coming in the next two months.
Alden can be a good actor, but that this film has dealt with more and more issues than it's worth. I take it that going forward, Lucasfilm and TWDC will have to change, following the division between TLJ and the production dilemmas of Rogue One and Solo, and that it'll affect Rian Johnson's new trilogy, the possible Obi Wan movie, Indy 5, and more as we go ahead.