It really depends on what you want to do with it. Are you going to war? Or are you just going to hit EBs?
Well, if your hola is to eb fairy and get gold, I would save up a ton of gold. You shouldn't be taking any Incs so I would say, save up 20-25 trill. Then you can make a conversion to an hfbc hansel. Then the plunder is way better
I'd build HL guilds then convert to vol because those SOS on LL will kill plunder earnings and make vols take longer to get.
If youre looking for stats, take down your sos, get your HF unlocked, then Put down ice trees 1 by 1. They don't kill plunder, like at all.
I had actually thought of this, too. I have 25 Guilds, with One forge. So, how much should I save up to? (Can you wall me, as I probably won't be checking this thread again)
since you are here: i would advise making an effort to re-balance the game rather than to leave a system in place that discourages the upgrade.