Leveling as a tank IS the best way to be a good tank at 85. Then again, who really wants to tank these days, the job sucks and they've made it easier for crappy DPS to cause a wipe (that the tank gets blamed for).
Also, "Minor: Doesn't particularly matter. Our minors are crap." is so, so, SO true.
At 85, I don't even bother to fill them. A minor to mitigate falling damage would be nice (you're not going to waste your bubble ...) Paladins have nothing except engineering tools to do this.

All minor glyphs are crap. Heck most are crap that should be baseline.

I have seen 2-3 minor glyphs that actually have a point. Even then, winter wolf is barely noticeable and you can live without the swim speed. Astral recall is the bomb tho.

All minor glyphs should be like this.

When I group up with anyone I tank no matter what class I am playing. I am not saying I am that great but it's just in me. Plus I am always playing a pvp/survival spec for leveling. I can say playing a prot warrior from level 40 on was the easiest and most fun I have had. Granted I had the heirloom chest shoulders and cloak (not til 70 something). Protection paladin is almost as fun. Having it been my first toon to max level I'm sure I did things (like gearing) wrong. I kind of want to level another paladin at some point and have started a couple.
If there are two things I can impart it is: 1. Get the heirloom tank weapon if you can. Tank weapons are hard to come by until you hit Northrend. 2. Keep a backup set of gear while you level for Ret or Holy. If it is your first toon, especially. If you have an 85 on the server you can always buy stuff from the AH.