Let's say the Switch pro could upscale games to 4k, has DLSS, slightly better screen and processing power. (Sort of like an upgrade from the 3DS to New 3DS) will you purchase a Switch pro even when you own a Switch already?
For me, I would get a Switch pro. Even if the difference is barely noticeable from the regular Switch, I want the premium Switch experience since some Switch games suffer from resolution problems especially the 3rd party ports, having slightly more clarity would definitely be nice. Plus I currently have the first model of the Switch with lower battery life, so if the Switch pro has about the same battery as the new model Switch that'll definitely be an even bigger selling point for me since I do sometimes get annoyed with the old model's battery life. Plus I feel like my Switch I got in 2017 is starting to age and is prone to get more problems as it gets older so I'd like a fresh new Switch. Also, idk why but i'd like to personally have 2 Switch's in my house, Switch Pro being my main switch and the regular switch being my backup switch or a Switch i could let my friends or fam use personally. I'm also a big Nintendo fanboy so it's one of those things where I'd just get it even though the improvements are miniscule. So I'd say the Switch Pro would be a day 1 purchase for me.