When it comes down to it barely anyone is playing granary blands and viaduct anyway. These aren't liked so there isn't really a reason to keep them over maps that are actually being updated other than you have played them for so long you are really good at them. Do you want something fresh and with potential to be better or do you want to continue playing (rarely) these outdated maps?
That being said I think there are new maps being made that don't necessarily have the potential to be good even with work from the mapper. Some of these actually do though. I think we should be honest about that.
Personally I do like product and don't really want to see it gone.
I think the least played maps should be removed, either blands granary and/or viaduct. The divisions should be weighted though to cater more to invite.
To end, I've made a handful of jump maps and have had a decent amount of comp players ask me to make a 6s map. From my pov it is not worth it at all, so it's pretty amazing to see anybody actually mapping for 6s. Kudos and good luck