The improvements are not quite enough to make me jealous, the only thing that would tempt me is a serious CPU/GPU upgrade. 1600p is sort of useless when you can't even run ps4-era games at that resolution.
I'd argue with FSR at that screen size it is not useless at all.
You watch video? It's super crisp.
You're playing a 2D platformer at native 1600p? It's super crisp.
You're playing a super demanding game? Render at 800p and either FSR or the fact that you're at exactly 2x scale with 1600p makes it so the image is super crisp as well.