I really like the design, just a little bit worried. If we do arches just for mentionable miners, what would we have to do for a renowned player? For a siege? For a Baron, Count, Duke and finally King? What would we have to do for a dragon attack or for the here who have slain the dragon? Death of the miner is a rather minor event in the DF. I am just concerned if our young city will not be built solely of monuments to fallen people?
As of other options here, there are plenty: a statue, a statue on pedestal, a shrine, a memorial featuring their picks in a weapon trap, a statue in a 1x1 room full of water with 4 windows. A statue on a 1x1 island, surrounded by water. A sacred grove. Name something after them (like mine, road, hospital, etc...). It would be a bit tricky to get proper statues of the people we want to memorize, but we can give sculpting labor to their relatives (Cain and Kerod) and they will sooner or later produce what we are looking for.
Those are just options, just so you do not complain that you are constrained to only building arches.
About searching for the new baby-maker - I have just checked the wiki, and it says that lover is irreplaceable. I wish I knew it before volunteering my whole family into the military... Anyway, that means that unless anyone knows how to fix that in dfhack - you will have to resort to adoption.
Dwarf4Explosives:
Sorry, but I am still not getting you. are you proposing to build our city like a up side down pyramid? And what/when/how that lever is connected? Why would we pull it if it would crumble our walls?
Or are you proposing building larger walls in advance on the supports and caving them in as needed to provide walls on the surface level? in that case it wont work. neither OOC (constructions do not cave in, they crumble instead), nor IC (imagine what would happen to any man-made building, including stockade, if it is dropped 3m down.)