I get what you're saying, I myself have questioned how wise our transfer dealings last summer were.
That's all in hindsight and down to the terrible luck we've had this season though. They were all transfers that improved the quality of the squad.
Kelly is likely cover, not a Botman replacement. Given how well the back 4 did last season and how with injuries they've struggled this time around, it's clear we need better quality backup. Upgrading Schar can wait a season or two, he's been absolute quality. That's where Tosin might come in once Howe has worked his magic on him. Also they're both free transfers aren't they?
I'm pretty sure Barnes was not a Gordon upgrade. He mainly plays on the left so if anything he was an ASM replacement with Gordon the flexible option up top.