Pile on your questions, happy to answer anything I can. Chester as a city is... not good. Like really not good, and not really getting better. Most recent is the Mayor dropping the N word and a 48 MM pension hole for a city whose entire annual budget is 58MM. Before moving to the suburbs I did take mass transit to the game (and you still can) by taking the Wilmington regional SEPTA line from center city to the Chester Transit Center. From there the team operates a free coach bus connection to the stadium, about a 5 minute hop. Back when I was doing it, SEPTA deployed a full SWAT team to the train station for security, and they umm, strongly advised my friend not to go take the "dangerous trip" to the restaurant that was on the same block as the train station, at like 3 in the afternoon. In otherwords, we would have been in view of an entire SWAT team the entire one block walk, and they were still like "guys, maybe dont". (That was on them, it was a perfectly secure walk... but it does speak to most folks thoughts on the city).
I now live 10-15 minutes from the stadium even with gameday traffic, in a fantastic Philly suburb (Media, PA) with great restaurants, good schools the whole bit. It's jarring how quickly it changes on the drive in.
Tailgating at the stadium is great, although they are tearing up about 1/2 the parking lot this offseason, so TBD... The stadium itself is more or less "detached" from the city, no crime issue to note. Locals are generally supportive of the team, and I always recommend parking in one of the local church lots to the stadium lots if you aren't tailgating... get these folks what you can.
The stadium itself is fairly bare bones/ basic, but the view is fantastic and the atmosphere is generally good and can be fantastic. True stoy: I got married about 10 minutes north of there on the river. I reached out to my season ticket rep asking (becuase what harm in there of asking) if the stadium was available for us to take pictures in, and then really pushing my luck... Could the groomsmen get dressed in the locker room. They checked, no one was using the park, and they didn't even charge me. One of the coolest things ever.
Biggest question for you is is it a day trip or an overnight, where do you want to stay, and obviously budget. Feel free to PM away.
EDIT: Anyone commuting from CC is better off with this bus than mass transit (if they run it again next year): https://www.upcomingevents.com/philadelphia/events/brauhaus-schmitz/philadelphia-union-soccer-game-bus-trips-with-brauhaus-schmitz-29739?ref=uceel