Hagerstown is a great park, with really good sight lines and a real "back in time" feel. The fans are super passionate and the beer garden is a great place to hang out and catch a game. It is kind of in the arse end of nowhere, with no public transport and very spotty Uber/taxi service, so for me that's a bit of a negative, because I would rather be able to stay somewhere nearby and enjoy as many beers as I want.
Harrisburg has a really nice park with a lot of interesting seating options. They have had some flooding problems this year (not surprising, given the location in the middle of the river), so the outfield is a little chewed up. If you get the LF/RF Bar Stool seats, you can chat with the outfielders (and unlike the CF barstool seats at Camden Yards, you still have a good view of the scoreboard). The Senators seem to really be trying to get people to have a good time there, with lots of little fan interaction games (Dizzy Bat Races are hilarious) but the crowds are still on the smaller side. The mayflies, well, you gotta see them to believe them. Beer is pretty cheap there (especially Troegs and ABC, their two big local brews) and it's easy to get an Uber or walk up the hill, over the bridge, and hit the Hilton.
Bowie has fantastic fireworks but a real nightmare getting out of the parking lot; if you visit, especially on a fireworks night or bobblehead night, park as far from the stadium as you can, so you can avoid as much of the traffic jam. It's a really nice park but the concessions are poorly run and lines are long for everything except towards the end of the game. Bring your patience and make sure your kids are well-fed when you get there. It's purely operational inefficiency, too; they have enough room and enough staff.
PNats are PNats
I love watching them play and I hate the stadium. Not a hint of shade anywhere. If you've ever looked at the crisper sleeve that comes with your Hot Pockets and wondered how it would feel to be riding around in the microwave inside one, go to a 5:00pm PNats game when it's above 90* outside and not cloudy, and sit on the bleachers.
