We are definitely not a real airline...no, but seriously nothing in your post even remotely mentioned the important stuff.
Engines under the wings, long flights, nice training facility?!? Who cares?
Focus in work rules and what the contract will offer you. For example: if you have a 13 hour duty day but only fly 3, do you only get paid 3 hrs for the day or are there further pay protections for you (its called rig)? If your trip has a lot of deadheads where you reposition from place to place as passenger a lot, do you get your full hourly rate? Etc.
I know nothing about Republic but I do know their contract is not bad at all. However, I just wanted to point out that there are far deeper reasons for choosing your place to work than the stuff at the surface. And my words come from someone who back in his 20's just picked a random airline called Air Wisconsin. Luckily for me, many winters I sat in a hotel during northeast blizzards getting fully paid for ALL my cancelled flights when many at the time, including Republic, where not paid a dime but were still at 'work'. Can you imagine if I would have ended up at a place like that at the time?
So yeah, do your homework, its a big decision. Air Wis worked for me. But you are not me. Only you can make that decision. I am often weary of places that make everything look pretty and dreamy. Are they hiding something? Why did they go bankrupt? Talk to people that work on both places and see how they like it there.
I will leave you with some advice:
1. Make the best decision at the time and live life knowing that at the time you made the best decision possible. People that live with regret are those who 6 regionals later and 10 years later are still on the right seat in a RJ with 2yrs seniority.
2. Here comes the irony: Don't take advice from strangers on the internet.