In ReaDelay I just select the vocal fattener and leave it at that.It adds a VERY, very, very slightly delayed signal to the original which does what a chorus effect does but in a tidier and less obvious way.
Compression going in - yeah I would BUT you can't undo it so it's probably best not too until you're sure about the result. Compression going in is GREAT for bass.
Definitely experiment with the Behri mixer's compressor, (I'm quite a fan of Behringer - I own several Behri items), on draft vocals etc. to find a setting that's smooths things a bit and you can tweak a little in the computer.
If you have a look at any software compressor it'll have an attack setting - the smaller the number, usually, the faster it grabs the dynamic sound - release is how soon it lets go Ratio is how much it compresses - 4:1 is popular for vocals. When I'm dealing with a very dynamic vocal I use two or three instances of gentle compression for a natural sound. If it's rock I'll use a couple - one that's aggressive and one that's gentle.
Of course singing a tight double track is the best fattener if you can do it. There are also some stellar ADT (Automatic Double Track) plug ins that do a fabulous job - the Abbey Road one is GREAT but expensive. There're cheaper & freebie ones out there though.

Cheers
rayc
"What's so funny about peace, love & understanding?" - N.Lowe