226
M9a1or3
Cz75

Can't go wrong with any of them.

I own and regularly shoot:
Beretta M9
Sig 226
Colt 1911

If I was going to buy another I would go with:
CZ SP-01
Browning Hi-Power
Or if I was feeling like dropping a ton of money I'd go with some fancy 2011 competition variety

I prefer and would stick with 9mm (.45 for my 1911 though)

As long as it's a quality gun and I had a few thousand rounds for training I wouldn't really care as long as I wasn't carrying it every day for work like my Glocks (used to carry a 226 but switched mainly due to weight and maintenance but I shoot and "beat up" my guns a lot)

There are still plenty of all metal handguns to choose from.

Beretta, SIG, 1911s, CZ, the Turkish guns, revolvers, ............as many choices as ever.

Shot my G17 today, I would not like to have to switch to any other pistol.

But if I had to switch to all-metal guns I'd probably go Sig.

still plenty of metal framed guns out there, only difference is there is a ton of polymer framed guns out too...

honestly, the only metal framed guns you used to find in volume and can't really buy new anymore are S&W 3rd generation (Police overruns of DAO models are the only exception) and the plethora of steel framed guns the Spanish used to make.   Oh and Ruger P-Series, but based on the prices of used ones, I think the Earth has a several hundred year supply of used ones...