Really the only thing that really is the challenge of this process is the RNG. ESP during the Dungeon Atma stage. Based on my two relics I've done, I can say with certainty the OP came out way on top with all of the excess tomes, seals and Alex. And during my two relics, I didn't use a single allied note. I got all mine from doing experts and buying the map with soldiery(actually have 90+alex now if I want to do another.).And when your getting tons of items to trade for GC seals, its not hard to get bomb cores, and still have plenty of room to sell Crafting items that you buy with GC seals. OP is likely rich as hell. Unless of course on all your zodiac dungeon drops you went 1/3 or better. Then I could see there being some necessary money, seal, soldiery grind. Most people I talked to all came out ahead. I'd really love to see your drop rate, but I doubt you kept track of that much of the process.
Id also like to know how much of this was done before all the nerfing to relic process, and how much was done after. It's really a much easier process now.
Grats on the achievement though. I'm jealous. If I didn't have a job, wife, and life I'd likely attempt this myself. I can handle the grind, I did 45 lost city runs and didn't blink(altho I raised hell in my FC /linkshells). And kept marching onward.