Man, you pretty much lost me with that entire post. I don't map out or do MIDI anything. I know absolutely nothing about MIDI or measures or soundfont or sequencers or synths or keys or any of that stuff. I couldn't even begin to understand that shit. I can't read music, time sigs, measures, bars, notes or anything. I know the notes on my guitar, but it really does me no good because I don't know any scales or what key anything is in. You can tel me a song in in A-minor and you might as well be speaking chinese. I'm strictly a self-taught punk rock drums, bass, and guitar kind of guy. I just plug in and let er rip. Surely my musical ability is severely stunted by my own self-inflicted lack of knowledge of even the most rudimentary musical theories, but fuck it. There's no room for techie shit in punk rock.
As for plug-ins, I use very few. But people way better/smarter than me rant and rave about Reaper's user-friendliness, so I imagine you just haven't figured it out yet. Like with music, I'm a computer dummy, so if I can figure it out surely anyone can. I use the Kjaerhus classic series free plug-ins and a few Reaper plugs. This Rudolph song here is about 45 tracks of various shit. Reaper handled it no problem.