Just keep in mind that tufts probably will work as mini VG's and probably improve the overall stall characteristics and lower the stall speed. They however should give you a good indication of how the stall breaks. I suggest you videotape both wings simultaneously to see how and when the flow separates.
If a rudder force is required in cruise it sounds like you have a fundamental design problem!
If the wings are adjustable you could also contemplate slightly different incidence on one wing relative to the other. This might also help alleviate currently required rudder force in cruise.
The key to stall recoveries is to ensure flow over the ailerons. When the stall breaks make an effort to stay off the rudder since rudder inputs might aggravate the recovery.
I would start with a full wing fence approximately 2-3 inches high in combination with either VG's ahead of the ailerons and/or boundary layer energizers on the leading edge. Just remember that the BLE edges must be sharp to shed a vortex. Use silver speed tape and try multiple configurations. When something works then start reducing or removing items. The key is to document what you do for later reference.
If your problem is positively identified as asymmetric only one wing might need treatment. Keep an open mind!
Small inboard stall strips might trigger the stalls evenly on both sides, but it does not sound you have much margin speed wise since strips likely will increase your stall speed. On the other hand a fence and VG's might lower your stall speed. The goal however must be to have the minimum amount of junk on the wings. Mounting the engine on a slightly offsett angle could also be considered if you already haven't done so.
Good luck!