+1 upgrade building mod needs to be brought back as a moderate gold prize, and by moderate I mean 20$ in gold.
These past 4-5 ltbs (excluding the slay belles) have all royally sucked for building iph and its making players simply upgrade them for the items they get while severely cutting the opportunity to raise iph.
+1 upgrade would eliminate the choice of whether you should build iph or upgrade the new crappy ltb for the prizes.