When you say 10v10, are you talking about the Sword map or the 4v4 maps? The latter I could see being subject to arty/offboard spam but to me, that goes with the choice to play under those conditions (ie, way too many points/players per frontage).
It's the same for both. Same amount of off map in a shorter amount of time. When your units are retreating for at least 4 minutes or so, it's pretty frustrating. Off map should be in the game and it's role is needed, but reducing the time for these games has made it's use way more devastating. Changing off map isn't what anyone is asking for, just give us more time to eat the damage and re-organize ( that means go back to 40 minute games ).