i think the CP boost for later joining is good.
The enemie Army re building and re storage of Buildings is BAD BAD BAD
Travian is the only strategie Browser Game where you can damage an enemie with catapults and bring him to ZERO
I am T3 Player and knew, the old days, where you needed 1 hour to re build Main Building, Level One and nearly one week to get your destroyed village back to a point where you can go on (with Gold Feature this can go much faster already).
So for Tactic Playing Kingdom vs Kingdom and in the Endgame Meta vs Meta this is Important to give abilyty to build Catapults.
We think next Round Players will only build Battering Rams and few Catapults for steeling Treasury and no one will attack WW any longer or go on Catapults to destroy Hostile Croplands and Core Infrastucture making Mid Game and Early End Game very difficult