I think both T8 and T12 have their place. I hugely prefer magnetic T12 (especially preheat) for use at home and I like seeing it in commercial applications too. However, I think T8 is much more practical for commercial use. I have serviced both T8 electronic and T12 magnetic fixtures in light commercial settings, and I must say that T8 is much less of a pain. I also have little interest in RS and Slimline stuff (ballasts or fixtures) made after the 60s. 70s egg-crate 2x4 troffers with 34-watt halophosphate T12s? No thanks!

Does T5 get no love?   I like T5, but only those that run on either a magnetic or battery-powered ballast.

HF T5 is good for commercial settings but I really have no interest in it. Magnetic T5 is cool; I have a couple T5 preheat fixtures that I like.

I found several NOS Sentry 40 watt air thermal starters from the 1940s on ebay recently and the information on the box said that the thermal starters extend the life of the bulb.

I installed two of them in my 1941 Fleur-o-ray 40 watt Double Paracyl fixture.
This fixture has the original 1941 GE ballast with the starting compensator.
The two new GE 40 watt K&B bulbs started up rather quickly with out any blinking at all.
According to the 1942 GE fluorescent lighting manual, the air thermal starter keeps a small current in the bulb filaments during starting and operation extending the bulb life.
Some of the first GE 40 watt ballasts had the thermal starters in the ballast requiring the ballast to be replaced if the starter failed.
After many complaints about this, the now familiar replaceable twist in starter was designed.
The air thermal starter was used originally by GE early on before the glow bottle starter.
 
They do work really well, but they do have a down side and may be it is the reason the glow bottle type starters were more popular.
While they do work ok, if you shut the fixture off, and then turn back on, the bulbs won't start again for about 60 seconds or even longer sometimes as the starter has to cool down before resetting itself.
This does not bother me, but for some applications, it could be a problem.
 

I like preheat and mag rapid start.

Am I the only member in this whole forum who actually likes those 70,000+ hour programmed start T5's?

I don't really have anything against them, and I'd trust them more than the LED tubes. However, I do prefer T8s to T5s as they make retrofitting a lot easier (better chances of classic fixtures getting saved). Plus, T8s can be had in ultra-long-life versions too. I think the new electronic T8s and T5s are quite practical (moreso than T12s) for general lighting, but as a collector, they don't interest me nearly as much as the old magnetic T12 stuff. When repairing lights out and about, I like to retrofit to T8 if the T12 ballast in a fixture fails, but I greatly prefer magnetic T12 for use at home.

I like all preheat fixtures the older the better. There is a place in town that has a 1950s vintage cryselco fitting still going I hope that I'd the owner ever changes it he will let me have it

I like preheat and magnetic rapid start t5/8/12, but no electronic instant start/ HO t5 garbage.

Thanks to the suggestions from some of the wise ones on here, I am starting to use Programmed Start & Rapid Start T8 ballasts much more often in most applications for retrofitting vs Instant Start.  I only use Instant Start where the lamps will be turned on once a day and for time frames of being on for more than a few hours a day.  Many of the applications I deal with have to do with fixtures that will only be on for short periods of time each day if even each day, save for Sundays when they'll be on for 8+ hours a day, and where they are used with motion detector/heat detection switches for on/off periods.  In which case the programmed start is ideal to save on filament damage.  I am already noticing a difference in lamp life by making such changes.