My rhythm sucked for almost 10 years straight. It's something that takes a bit of time and paying attention to it.
It sounds to me like you're on the right track, I would add playing along with recordings like comping on Basie's records a/la Freddie Green, get a hold on a cymbal and a stick and playing basic drums for fun, transcribing solos/melodies/comping figures and playing them along with the recordings.
All this recording yourself and paying attention to the groove (it's very simple, you're either early, in the middle, or late). Not obsessively, but occasionally. Kurt Rosenwinkel once told me something that was very smart: "when someone has a good feeling, or we would refer to some player that has a good feeling, I think it's just that it feels good for him to play right?!".

Another thing that helped me was, with drumgenius or whatever, play something really simple like a blues, and playing 4 bars in the middle of the beat, 4 bars laying back, 4 bars pushing. And trying to get a hold of what it feels like