I'd suggest the Glock 23 40s&w.
Its ballistically similar to the .357Sig, but 40s&w ammo is much less expensive.
The G23 can swap to a 357Sig or 9mm aftermarket barrel in seconds, works great.
But it is a Glock - No manual safety.
Its not going to go off because you look at it wrong or even drop it, but you really must have good trigger finger discipline or you will shoot a hole in something.
If you have the basic firearms rules down, and keep your finger off the trigger, the G23 would be a great first pistol with lots of versatility.