Re: The "Triumphant" ones should know...
Apple: meet Orange. Orange: meet Apple. Now go to your corners and come out fighting. And may neither one win.
In other words, there's no comparison. Back in the day, Sprites were very much entry-level sports cars: basic, light, decent power-to-weight ratio, very tossable and enjoyable. TRs weren't quite the opposite, but they certainly were significantly upmarket: bigger, more powerful, somewhat better appointed, arguably a bit less of a "toy"!
Presumably you already like the Sprite. There's a very good chance you'll like a TR2 or TR3 just as much but for very different reasons. Over the years I've driven several of each, along with Spitfires, GT6s, MGAs and MGBs, MG-TDs and MG-TCs, and a few others (notably Datsun 240Z). Don't ask me to pick a favorite; I always found plenty to like with every one of them. Choosing any of the above on a given day might depend on mood, barometric pressure, stress level, who's on Letterman that night, where the Dow-Jones sits, etc., etc.
Of course, it's all much easier if, like Jay Leno or other big-time collectors, you can "have them all"! But from what I've seen on his web site, Jay seems to get almost as much of a kick out of his Fiat Topolino as he does his modified Toronado...or anything else in his fleet.