TH 9 upgrade order

I have all splash damage upgrades done for th 9 (wiz and mortars) and now I have moved on to the xbows, I have one of them upgrading to lvl 2 and I am saving up the 5 mil to upgrade the other. After those xbows finish, them and my splash defenses will be the only things I have upgraded to their new available level, meaning all other defenses are still the level of a maxed th8. Should I save up for level 3 xbow after they are done upgrading to level 2 or should I start getting cannons, teslas, and archer towers upgraded before I bother with the level 3 xbow?