I juste played a game yesterday against 2 Reg. Remember Reg's main weakness is he cant' stand 1v1 against almost all other DG, especially generals. With low armor, low HP, he 'll often try to attract you into towers; never go there except if you're at least level 5 & if you feel you can kill him. Just keep the flags and up your warscore; get a little back, they'll approach the flag and chase them until they get to their tower, then back, etc.
Mines are a problem? Send your minions into it, like StAcK3D_ActR said. Snipe is a problem? Never get under a certain amount of life.
If your builds are good enough and you stack sufficient amount of life & armor, they shouldn't be able to keep control on flags against you.