[Helix_FR]

The best I can suggest to get what you want and can serve you well across the board no matter what you shooting, is get one with removable choke tubes or get one that can be converted to removable chokes. Not poly choke, they are too inconsistent. That way you can change your patters depending on what your shooting. I shot competition trap trough college and did it with a 24in barrel Ruger Red Label. Its what fit me and the short barrel made for quicker shots and acquisition. Many of the other shooters had their trap guns with all the high ribs, some autos, some doubles but I did well b/c my shots were so fast b.c I wasen't dealing with swinging a longer gun. I ran Full over Full but at any time I could change to something else b.c I had removable chokes. I'm a big advocate of doubles but get what suits your needs. Many people like autos but they are the first to fail you. Much of what your get also depends on price. Mossberg and Stoger have doubles in the 500 range. CZ, Ruger, Brownings are in the 1000.00 range and up.
If recoil is a problem, moving to a 20 ga or even the 28 ga would do you well. 28 ga is getting more and more popular among the ladies. CZ has a gorgeous 28 ga O/U that is a case hardened receiver and black blue barrels. I keep eyeballing the one for sale by my house.