Which aeroplane? I have not a slightest idea.
However, I know a couple things you should do.
First, give yourself a big pat on the back. Landing a job today is a very big deal! And you get to choose the aeroplane - lucky you!
Now that you have decided that the airline suits you, you might think that you'll be making an informed decision about the fleet but this is actually a harmless delusion. The only aviation constant is that it changes incessantly. The 145 guys get fatter paychecks now but that might change within weeks and stay so for years. Or not. Hours required for captaincy may shift both ways. How about the bases? One type might get better base, but basses move and close too. 145 today looks to small for feasible operation but who knows what the next economic f-up might bring, maybe point-to-point flying with 40 seat jet will be the hot thing. And if you choose to move your business, will your future prospective employer look at 145 as serious jet or will even 190 will not be big enough to give you credit for flying it? Will the pilots with classic experience be more valued than FBW guys at the marketplace or v.v.?
All this stuff is mostly unpredictable in short term and totally unpredictable in long term. If you get on the side of the fence with browner grass, don't berate yourself for it and if you get on the greener one, don't congratulate yourself too much either. Whatever happens, there will be people whose wild ass guesses have turned correct and consequently have very high opinion of their analytical capability. They will either chide you for your bad decision or flatter you for your good one. Recognize them for what they are, don't take them too seriously (but don't show it openly if they're senior to you) and resist the temptation to become one of them.
Whichever bird you choose, without having flown a single hour on either, I'm pretty sure they're fun to fly so enjoy your flights.
And use sunscreen.