I've taken a look at your room and you don't have a lot of space. Here are some ideas from me, just to start discussion. They're in no particular order and just me brainstorming:
1. Overheads - you're going to be closer to the kit than you would be in a bigger room. If you can, try large diaphragm condensers. Do tests in XY and ORTF and see which you like. It depends on your side walls, but XY will probably be what you choose. Since you won't be able to raise / lower the mics, you'll be stuck moving them towards the drummer's head / away (towards the toms/kick). Spend time finding where the OHs need to live on this axis. This is critical. You need the right blend of kit vs. cymbals, and this is one your only areas where you can move the mics freely.
2. Orientation - again, there is where the kit seems like it should be set up and there will be where the kit sounds better to the microphones. Sometimes they are the same place.
3. Hi hats - probably don't need to mic them in this room. Bleed will get them.
4. Close mics - try to get the best isolation you can with them. If you use condensers on the toms (vs. dynamics) remember that multipatern mics (e.g. AKG 414) in cardioid mode have less rejection that an cardioid only mic due to the acoustic shadow effect of the back diaphragm on the multi-pattern mic. So, either stick with dynamics or use fixed cardioids if you go with LDCs.
5. 2 passes. This is an old technique, but one still used by the likes of Omar Hakim (who records drums in a small space). Record the drums then play back the mix through a speaker in a larger room or in the room no drums and record that for your 'ambience'... fold back into the mix. Of course, you could use a reverb plug in, too. But its worth a shot. I've even heard stories of bands recording with the drums going through a PA system to get a larger sound. I wouldn't want to sort that feedback out, though.
I agree with you on the replacement thing. Yes, it would work, but you seem to want to use recorded sounds from your room, which is a very honorable goal.
Keep going!
GH