1. Adding momentum to jetpack. Remember grangercannon, when you launched from the jumppads, using jetpack while flying immediately canceled any movement. So instead, why not keep a part of your momentum, making the jetpack a little less maneuverable, but still possible for most people to use and for noobs to jetcamp, and for jetcampers to die more often due to their path being more predictable.
2. Either overheating, ammo reload, self-damage or minimal range/deadzone added to f-lamethrower, with finger extended to people who stand one place and continuously spam flame into the door, preventing anything smaller than goon to come out.
3. Automated !warn to people who run around flaming everything but not the Muffin driven mara, without paying any attention to friendly fire. You flame 20hp+ you get !warn.