Wingmaster, SuperNova,BPS, would be my choices in order .
Wingmaster is a do all very reliable pump gun with a million after market accessories . Nicely blued and polished from the factory . With the express 870 you may find yourself having to polish the chamber as as many feature a rough chamber that causes grief ejecting shells. Express models seem more prone to rust also.
SuperNova is a basically industructable pump that handles 3.5 inch shells if you choose, strips down for cleaning in the field with zero tools, comfortec stock is cool and deffinetly reduces felt recoil , shims to adjust the stock to your liking are all so a bonus . It is a heavy gun though, pump stroke is long for some peoples liking, also asseccaries are scarce and costly .
BPS (Browning pump shotgun ) is a great bottom eject shotgun perfect for a leftie. Accessories are fairly common, love the tang Thumb Safety, one big negative for me was complete tear down and cleaning as it can get trickey.
A newer Ithaca M37 is a cool option if you can find one threaded for chokes for more versatility , bottom eject and they have a slam fire option ( hold the trigger and pump away) you'd likley never use it but kinda cool. Newer M37s also seem to have some of the nicest wood on a pump you'll find .
Wood vs Synthectic ......
In my opinion Wood stocks are deffinitly nicer to look at but having owned guns with AAA grade walnut stocks I hated smashing through the underbrush of a grouse cover trying not to mark up the fancy stock. Even though scratches build character on a stock, it still hurt.
I've since learned to love just plain black synthetic for the pounding and crappy weather conditions it can take .
The most important thing as others have stated is make sure which ever gun you choose shoulders nicely and feels right.
Just my 2 cents , good luck
Ry