Flak or kinetic, charge, and as a weapon I prefer Cosmoses there. Blueshifts are also great and other people will probaply say Nebula's are the way to go.
That honestly depends on what you're defending the base against, and at a tower you'll get all 3. I'll list my favorite loadouts here and why. Hopefully we can get more comments on it. Anti-Aircraft (AA) Weapon: Dual Bursters with ONE extended magazine --This will allow you to have continuous fire because after your smaller clip burster runs out the one with the extended mag has enough to last through the reload time of the first. Eventually they'll eventually drop out of sync if you maintain continuous fire for too long but that requires more ammo than you carry and either a TON of air or a very very stupid galaxy pilot to stay in your line of fire. Armor: Nanites or Flak --Flak allows you to take hits better, Nanites will cover for a lack of engineers and rep you when you're not being shot. I personally run Nanites, but flak is a good call too. Special: Zealout Overdrive --Increases damage dealt (and taken) for a short time...nothing says "HI!" better than a ZOE Burster. Anti-Vehicle (AV) Weapon: Dual-Comets --These hit really hard, especially with ZOE. Vortexes are probably a good call for long range AV matches though. Armor: Flak --Yea, you'll want this. Unless you're on the ground running around without engineer support..then nanites. Otherwise Flak helps absorb enemy tank rounds. Special: Zealout Overdrive --Scares folks with comets. You'll get their attention reaaaaaally quick. Which is good because the amount of attention they pay to you is directly proportional to the amount of damage you're dealing their sunderer right now. Endurance Max (Anti-Infantry (AI)) Weapon: Dual-Cosmos with BOTH extended magazines --Extended Magazines bring each clip to 112 rounds. 112 in your right, 112 in your left. LOTS of bullets. Armor: Nanite Autorepair --It's called endurance for 3 reasons, the first is the extra bullets in your chamber, the second is for the MAX's ability to repair itself, and the third... Special: Ammo Storage Canister --Yea....you'll have lots of bullets. With extended mags and ammo storage canister 4 I can hold 112 rounds in each gun and 648 spare. 648. For each gun. Firing at max capacity continuously, with breaks only for reload, it takes 2 minutes and 36 seconds to run dry. Firing continuously, alternating weapons for maximum fire duration, it takes 4:26 seconds to run completely out of ammo. That's almost 5 minutes of non-stop fire. While that's not a realistic situation, it does mean that you'll almost never run out of ammo on your own, and combined with nanites, you'll never need an engineer to repair except perhaps in the middle of a firefight that you can't duck down in.
Depends on what you're defending against. If you want to hold off vehicles at range from that tower then I suggest using Vorteces. If you're keeping infantry out I suggest using Nebulae with extended mags. Though Nebulae will restrict your effective range, so you'll want Charge to close ranks. The good news is that it's pretty cramped in a tower. As for everything other than weapons, I say it depends on your playstyle. If you're mostly solo then I suggest using nanite auto repair. If you can count on an engineer to keep you repaired, then go with kinetic armor. Kinetic armor and extended mags will also give you a fighting chance against a scatMAX. So: Long-range Anti Vehicle Defense Vortex Flak Armor Charge Tower Anti-Personnel Nebula Extended Magazines Kinetic or Nanites Charge That's my 2 cents.
