First, you should have stayed at HQ 8. It's the best and safest HQ level to be if you want to play Events for Elite frags, do Heroic Defenses/Daily Objectives to improve your Armory for attack/defense, play Wars if you do not have the obligation of attacking 10s and Prestige bases, and PvP is not hard if you aren't maxed out on your defenses or keep your medals at a low number.
But now it's done. If you are maxed out on defense (turrets and traps at high level) or have a great number of medals, you probably are fighting 10s and 11s right now, and it will be hard to win attacks, even harder win defenses, untill you upgrade at least your basic troops for attack and Transports unit/SC.
At level 9, you can unlock the Luggabeast to help in your attack loadout. You can build the Oppressor, and your SC can fill with 5 jumps instead 4 if you have the skins for jumps. If you don't have the skins for jumps or don't have them at good level, you are dead.
For players that didn't play conflicts for new special units like the Imperial Transport (that deploy dark troopers) or the new SMTT (that deploy Dowutins), you will need to use Jumps with the skins (earned in Bronzium Crates for Heroics and Objectives) and Hover Tanks with the TXs skins (earned in War Crates and Events from time to time)
The rest is infantry like Kubaz for the shields, shock troopers to clean the way from traps, mercs like gamos to shield your heroes like EATAT (with the skin in green planets) and Vader (with Lord Vader skin), and air. a lot of air.
SWC Windows survivor.
Imperial HQ 11 & Rebel HQ 11 on vacation.