The CME is a bit more expensive, but is built like a Sherman Tank!!!! Made with real METAL, not cheap plastic. It just feels better all around too, even things like slider durability, etc. It all feels so much more top-of-the-line.
Kontakt will work with Logic, at least Kontakt version 1. But each new VST plugin released usually offers support for the newest version of VST technology itself. And obviously Emagic has long since abandoned us here. I agree the EXS24 is a little hard to get your head around unless you spend some time with it (Which I have oddly found to be the case with Halion and Kontakt too...Only Kontakt because of the extended features it has compared to the others).
I'd suggest if you are going to move away from Logic, then try Cubase. This is the move I made, and I'll be honest, that after spending so many years in the Emagic camp, that I really thought a lot of the Steinberg workflow was just assinine. However, Steinberg has been thoughtful enough to allow you to map all your shortcut keys to match those of Logic, with the click of a single preset, which is definitely a nice touch, especially if you move back and forth between the 2 apps (as I do because VST technology still doesn't support side-chaining....(soon I hope), and I like Logics MIDI Logical editor better than Cubase's). But all-in-all Steinberg has the goods. Somethings will take some getting used to, but after working for just about a year in Cubase, I realise now that most things are just easier to do in Cubase (Especially in the audio editing, and file management departments, which Logic only really started to address, after the Apple buy-out
). And with Steinberg you are assured of getting the latest support for new VST technology, so should you encounter a problem with your plugins, you'll be getting up-to-date support.
Get Kontakt, Get Cubase SX (But maybe wait and see if SX4 includes VST 3, which I guess is rumored to support side-chaining (For compressors, gating, etc.), or go ahead and get SX3 which still kicks ass), and start down loading drum samples, and rock out until the cows come home.