I understand the concept of only ever needing to record one or two inputs at a time. I'm in the same boat myself. I am never going to record a full band or even multiple musicians in a single take in my home studio. Never. One or two mic inputs is plenty for me.
But when I upgraded my interface last year, I bought an RME UFX with 30 ins and 30 outs and I still feel it was the best choice for me. Because its not about needing to record live mics, its about having tons of extra ins and outs for whatever outboard gear strikes my fancy.
Plugins are great and have lots of utility. But IMO, there isn't an 1176 plug out there that truly measures up to what the hardware can do. You can get more plugin reverbs than you can shake a stick at and lots of them sound fabulous. But none of them sound quite the same as the old Lexicon hardware units. And while those old Lexicons can sound a bit dated today, its still a sound that I like and use.
Now I can already hear all the folks out there saying 'I don't use outboard gear and I never will'. My response to them is simply this. Two years ago, I said the exact same thing. Never will I use any outboard processing or other gear in my studio. Never.
Then I stumbled onto a great deal on an old lexicon and since I had those digital I/O's that I wasn't using on my interface anyway, what could it hurt. Then I decided to build one of those 1176 kits. That first kit led to a second and I've already have all the electronic parts for a third. That's how it happens and it can happen to anyone.
So I'm in the same boat with OP, I don't really understand the obsession with the one-knob devices. I like having options and a one-knob seems like the opposite of that.