You want a light hub with fast engagement and don't want to pay much for it? doesn't sound like you're asking much
It is quite an ask to find a light, cheap hub with quicker than average pickup. XX1 shouldn't cause any issues as the vast majority of manufacturers should have solutions. You should be able to buy hubs with the XX1 driver fitted as standard so shouldn't have to factor a new freehub in to the cost.
CK is hardly light or cheap. I wouldn't call DT 240 cheap either although they have a great reputation and most people seem happy with the investment. Kappius is light with one of the fastest pickups but not cheap either. Maybe the best option is to go to a site like R2 Bike/ Dulight/ Starbike and browse through the light hubs until one jumps out with the right balance of pickup/ weight/ price for you.
I guess it is easy to find a light, cheapish, reliable hub if you can settle for an average number of teeth in the freehub. Personally, as nice as a quick pickup is, it isn't the deciding factor for me and makes very little difference out on the trail IMO so it was easy to choose American Classic when looking for a light, reliable, good value hub.