I consider corruption and quality of services "easy" problems if your economy is growing and your democracy is improving, you just need time. The richer you are, the less likely are you to accept bribes.
City design can be a harder problem depending on the specifics but ultimately still solvable with time.
Population decline due to emigration seems like the biggest problem but maybe it will naturally self-correct, I don't have a clear opinion on this. I live in the Czech Republic and I have to say we're lucky we evaded the emigration curse that's affecting most ex-Eastern Bloc countries.
Emigrate where?
I even remember a recent news that a drugged guy that was 'checked by police' several times, they found drugs but didn't want to test him for drugs, killed a bunch of ppl with his car. Or the case where a lot of ppl burned alive in a club bc of the way it was designed and till today nobody's imprisoned, or when a bridge collapsed right before a school bus(bc they've stolen the money), there wasn't tragedy, but it could have been, and still, nobody in prison. Totally thriving county!