Coelocanth: I like FTR/PAL/CoT or PAL/Rogue/CoT. 4 levels of FTR in the first combo to get Weapon Specialization. The number of CoT levels depends on what abilities you want and how many extra feats you feel you need. For the Rogue build, I tend to stick to only 4 levels of Rogue by level 20 (yeah, it's a cheesy powergaming skill-dump build).
SoU will take your character to level 12 or 13. By the end of HotU you'll be at level 27 or 28. Keep that in mind when planning your build and you'll be fine.
So, which is more important to take WIs 14 at the beginning with the idea of getting 4th level Paladin spells, or taking more CoT levels? I have seen a Divine Warrior build where you start with WIS 12 and end up with first level Paladin spells. Both are intriguing. The former works off the build I began in the OC, using the Holy Sword spell and Divine Might.
Does the Holy Sword spell stack if using a Holy Avenger already?