Simply allow users to upgrade walls even if there isn’t a builder available.
I’m becoming a th9.5 currently and I’m just upgrading traps right now. Once I’m done with those I’m on to walls and that’s it, but in the meantime, I hate sitting around with max gold or elixir as troops are being researched in the lab and buildings are being upgraded.
This would work both in builder base and in normal base. Allowing users to not have to have the loot taken, they can keep it protected investing it in walls whilst the builders continue on doing there jobs.
Allow walls to upgraded when builders aren’t available.
A long time ago, it used to be like this, but Supercell changed it because it had a negative effect on the economy as a result of players dumping their excess loot into walls.
My suggestion would be to have one Builder available at all times to upgrade walls with.
As dardanius said, keep a builder free for walls. I've done this since th9. Had no problem getting walls done along with upgrades. If you manage your builders, walls should be the least of your worries. Especially after the cost decrease.
