I think you'd be best off with the 2004-2020 Sienna because of the superior reliability. The V6 has been around forever, so it is proven. If you want AWD, that is also available in the Sienna. The Odyssey seems like it either has engine or transmission problems for every generation.
But honestly, none of the minivans will really be hard to DIY. I think the Dodge GC and T&C with the Pentastar V6 are also pretty easy to fix, and the price of entry is cheaper than the Japanese options. They aren't as high quality though.