That's why I need advice. Should I heavily equip both attackers and defenders? Should I add more entrances for the attackers to attack through? What?
Perhaps a platform reaching out from the attackers base to the defenders base, which you can't drop down from but can cover those below from above through windows. For the love of kittens don't put shield doors in and give the attackers shotguns.
I think you do need more entrances for the attackers, so far the defenders have it too easy. i agree with the idea of a ledge overhanging teh defenders base, that you can shoto from but nto jump from. Have mabye a lone sniper with one clip up there so the attackers cant snipe the whole defending team. Also have a counter weapon for defenders. Infact scrap that, start the defenders with the sniper, and put a spartan laser with slow respawn for the attackers up the top. Add 1-2 more entrancers for the attackers, so defenders have to cober more exits. Id suggest having both teams heavily armed, but make sure the tunnels dont ebcome just camping spots, if you have a coupel fo shoutguns for teh attackers, make sure there are a coupel of brs for the defenders comign across teh open space. Also a lone turret for teh defenders could be usefull, as ong as it has a weak spot, such as an exit to one of the sides. On your sketch te two tunnels that lead to the back could do this, have teh turret infront of tehm in the middle, so these tunnels flank it. Giving teh defenders another worry, and teh attackers a bit more of a chance. Just my opinioun, i have a few otehr ideas but i need my sleep now! Oh and sorry for my increadibly bad typing, just got in from teh nigth shift lol