Well, if you want a 45, get a 45. I was a 45 guy for a long time and still am to a certain extent though I rarely carry them these days. The 9mm has taken many lives. Many, many lives. I have very little doubt that .355 and .357 caliber handgun bullets have taken far more lives than .451 caliber bullets. I don't really think this is a valid argument though as the only bullet effectiveness that matters is yours.
I guess it boils down to this... a well placed shot from a 9mm can certainly be a decisive fight-stopper. If you have confidence in your gun and you can conceal it and shoot it effectively, then I would stick with it. It sounds like you either aren't confident in the Taurus and/or the 9mm round or you would like a bit slimmer gun. Or maybe you just want another gun. Which is just fine!
I have put more rounds through my Taurus PT99 than any other centerfire gun I've ever owned... Probably more rounds through it than any
three guns I've ever owned. I usually say 18,000 rounds but it's actually probably slightly higher than that... FMJs, Gold Dots, CarBons, Tritons... I have never had a failure to feed or a failure to eject. I cleaned it after every range trip but sometimes those trips involved 300 rounds of ammo and countless presentations. I dry-fired the peepee out of it and I've probably put $60 in replacement parts that, while prudent, weren't needed at the time. I've owned a lot of 1911s including several that have never had a failure but 18,000 rounds is a lot of rounds... a lot of confidence-inspiring rounds.
If something was going on outside my home and I happened to have all my guns were laid out, the Taurus loaded with 5 CorBons and 10 FMJs is very likely what I would grap.
Do you hunt at all? Or maybe know anyone that picks up roadkill? If you do, I can give you a couple pieces of advice that might help build your confidence in 9mm.