Sorry, didn't mean to muddy the waters

When it's just a team of two, I'd want to maximise the DPS for quick kills more than worrying about healing.

What you're suggesting is just fine. Two of anything is pretty much just fine as well.

The one real advantage of starting off as you originally intended is that I imagine you'll be "driving" your pally tank most of the time once you have five characters, and that's something you'll already be used to.