Obviously rewards need to be given a little more love. I think to address that two things need to be done
1) Add "exciting" rewards that require lots of Tyrian Defense Seals (expensive crafting mats like amalgamated gemstones or mystic coins, obviously in moderation, OR cosmetics like an infusion). Maybe also consider adding a guaranteed way to get Volcanic Stormcaller weapons for a huge amount of Defense Seals to encourage long-term play of the missions.
2) Add "worthwhile" repeatable rewards. The supply boxes we currently have don't get you much bang for your buck. You can either reduce the Seal cost for these a bit or add a new repeatable reward that's a better deal.
Then, the gameplay of DRM's could be adjusted to make them a little smoother.
1) NPC allies, especially those related to the ["ally support"](https://wiki.guildwars2.com/wiki/Dragon_Response_Mission:_Metrica_Province#Allied_Factions) mechanics, should have their vitality and toughness increased and/or auto-revive over time. Currently they die too often to bother keeping alive.
2) Once the pre-event is complete, the DRM should progress immediately. Waiting out the timer is easily the slowest part of any DRM.
3) Reduce the cost of recruiting an allied faction from [Meradh](https://wiki.guildwars2.com/wiki/Meradh), 10 Seals is too much.
Aside from these changes, I think we should wait and see how the next couple masteries we get impact DRM's. If they're particularly powerful, the pacing issues might be alleviated.
EDIT: Also reduce the cost of the Bead of Liquid Karma. 10 seals for 500 karma is not great lol.