The main thing you need to do is go to a range that will let you rent/shoot as many differeny kinds of pistols as possible.
One thing(among others) that I don't care for with polymer framed pistols is the fact that most of the weight is in the slide and barrel. What this means is the recoil,altho not bad at all,will feel sharper than with alloy or steel framed pistols because most of the mass weight is moving back quickly and then returning to battery.
Without knowing your budget it's hard to really help you choose. One example is the excellent para ordnance lineup of 1911 type pistols. Altho it's not faithful to traditional 1911 single actions,the LDA line offers the best of both worlds-1911 AND dao. The trigger pull on these pistols is so smooth and light that the very first time I shot 1,I thought the darn thing was broke. Be forewarned however that they are a bit pricey when compared to other factory pistols(600-800$).