The information about a 2" caliper being about 'top end' for transplant without delay is what I am looking for. [...]
I've seen 'bare root' trees online. But how are they compared to potted? I'd rather support my local guys if possible, but that $$$ must be reasonable. If there is a premium for a local potted that outweighs its true benefit to me, I'd rather not. But I'm willing to give a bit if its worth it. However, If I can buy more/better bare root trees online, I'll do that. I don't have the $ to simply waste on sentiment.
I am not sure you will find bare root trees in 2". I have seen them in fruit trees about 1/2" or so, but they top out at about 5' including roots to fit in a shipping box. A 2" hardwood tree is going to be too tall to ship easily, I suspect what you will find for them will be potted.
The bare root fruit trees get established very fast, I would guess at about two years you are about where you'd be with a larger potted fruit tree, at a lot less cost.
If you are putting value ahead of everything else, I would put a premium on being able to pick out your own trees rather than relying on luck-of-the-truck. Every place will tell you they have a replacement guarantee. My unhappy redbud even had some super duper multi-year warranty from an excellent nursery...they were out of business in less than a year, just couldn't keep up with the box stores, so that warranty is useless. Pick a good healthy tree from the start.