I'm guessing this has been on a lot of your minds, as I've been asked about it at least three or four times now.

I probably won't be doing another comic with Gem and Lazuli, since it would basically be the same thing over again, but I do have plans for many more comics like that one in the future. Brother to Brother is very much a black sheep of the “series” since legitimate romance and/or love plays little to no part in it, and in the rest of these I plan to mostly stick with the same sort of tone that Keep Me Warm had (not to mention Gem and Bloodstone aren't a canon pairing while the rest of these are). I'll most likely keep these comics in the same visual style as Brother to Brother.

Currently I plan to do comics of:
Gem/Chillie
Drika/Haru (male/female Shadow Flygon couple)
Cutlass/Damascus (Pawniard sister and brother)

Currently I'm CONSIDERING doing comics of:
Hoodie/Saturn (male Scrafty and female Charmeleon)
Bloodstone/Rick (male/male shiny Sableye couple)
Drika/Charberus (female Shadow Flygon and male 3-headed Shadow Charizard)
Chalky/Paschel (male Sableye and male Lampent)

The least likely of those is probably Chalky and Paschel since there's not a whole lot that can be done with those two, but it would still be worth a short comic at least. If you have any questions, feel free to ask.