More duel game modes
This game has one usp and that is 1vs1 duel. This should be the focus of quake live to make it stand out if it is to survive because right know it isn't cutting any mustard at all. All other game modes than duel are easily surpassed by other games for at least 10 years now due to advances in game design, player base division and other factors. This fact will not be solved by adding more maps or more game modes that no one play.
Focus one adding some 1vs1 game modes that are easy to learn and fun to play even for players with a skill gap. These should also be steps to the current duel game mode.
Example game mode:
Plays exactly like current duel but instead of scoring when killing the other player, you get the "advantage" if you don't already own it. The player that has the advantage when the time is up wins the game. One player is randomly assigned the advantage at the start of the game.
That's it! Easy to implement, easy to understand, a little more random but more fun and exciting for the casual player. Could even make it TL5 also.
Also make an insta-advantage variant.