Guilds/Groups should, at least mentally, have three options when queing.

A. Competition: true GvG.
B. Training: GvG or PuGvG. In either case it should be understood that the group is trying some things. Maybe completely new or off the wall. The group isn't garunteed the win, it's just trying to get better, thus all cylinders aren't firing and a total PuGstomp is less likely to occur.
C. Casual Play. Nothing is for keeps in the game. Groups should be encouraged to do some things that are kinda rediculous. Like, for example, Orks V LSM can be ENTIRELY melee with Shieldwalls. I for one want to see a Fortresses entirely fought over by melee. No guns, turrets or tanks, literally just 60 people in Shieldwalls formation.

Here's what about 30 people doing that looks like.



That requires guild coordination. That level of awesomeness would require multiple guilds. More than likely cross faction guilds. And to give creedince to the OPs argument, that side of the community is strictly against this sort of involvement and it's time to change that. It has been time for this change for a very long time. Too many of us have been focusing on the personal projects rather than the community one's. Too focused or far removed from each other to get past pride, prejudice, Xenophobia, trolling, or past grievances people carry into grudges.

Having fun should not be difficult. Extend the effort and organize a time to have fun with each other. Ride on top of tanks, build Shieldwalls. Damnit I've tried for so long to show people a good time in this game, it's not hard to do when you put aside the competitive nature and focus on your community. But you have to commit to it. Communicate it, and have everyone else on the same page.