I've spent a long time with similar problems!
Best bet for me has been to work with a real live drummer but it's not practical at the moment. I know that you can collaborate remotely if you find the right person, but I've never tried. Could be an option.
I tried learning with an e-kit and while I enjoyed it greatly for a couple of years (!), proved to myself and my neighbours that in the end I'm really no drummer. I quite like sequencing with hardware (mainly a JD-Xi and MPC) but that doesn't usually give all the live vibe/layers I want.
I had a BeatBuddy for several months. It was a good piece of kit, and useful live, but ultimately I sold it on. What BB doesn't do is help in generating patterns in the first place, which is ultimately what I'm after.
I have Superior 3 (upgraded from EZDrummer 2) which is great. The editor is a boosted version of EZD2 - it also has a grid editor, so you can mix and match - but what I've found really helpful is to run Jamstix into Superior.
For those who don't know it, Jamstix is a VST which takes your basic groove pattern (a MIDI clip you build or import) and tweaks it based on modelled drummer behaviour - timing/pocket, fills, accents, and so on. You structure the song in terms of parts (intro, verse, chorus etc) which can have varying power levels, timing offsets, frequency of fills and so on.
It's highly adaptable: you just have to set the parameters you want (for example, likelihood of preceding a fill with open hats), let it do its thing, repeat play until you find something you like, lock down parts and move on.
The downside with Jamstix is (1) it's not terribly intuitive (it's really a case of print out and RTFM, especially the song builder and brain sections; there are some useful videos too although not many for the current version 4); (2) it's not gifted with good looks, and the UI is fairly clunky in use (eg very little drag and drop available), but that doesn't really matter to me. Oh, and (3) it's not free - $99 for the basic (fully functional) version, which is fine for using the main features, especially if you have other drum software to run JS into.
In the past couple of days I've made convincing drum tracks for two songs with Jamstix (and Superior's kits), in a way that's been quick and fun. I tend to use the Loopey drummer model (there's a whole bunch, from Charlie (Watts) to John (Bonham) to Stewart (Copeland) etc, and all are configurable) because it doesn't do too much to the beats (I like simple drums), but can generate fills/accents with a vibe I like. Worth a look.
In terms of integrating with the DP - I have a DP24, so I can and do sync Reaper to MIDI which is fine. And there are workarounds for the DPxxSD models to generate clock I believe.
However, usually I'd either have most of my non-drums on the DP24 anyway (recorded to say an MPC beat, which would be on there too) and export the lot to Reaper to work at drums; or maybe start with the drums on Jamstix/Superior (or EZD2), and export the mixed WAVs from the drum VST to the DP24, then go from there.
Stew