Pixel 5 here:
- 20-30% more battery life than the P5 when it was new (my P5 battery life is still very good like 90%-95% of when it was new). But I don't want to have the excellent battery life I had in 2020. I want something better.
- Lower price than the P8 (so I'll wait for a discount if I upgrade to that one).
- Better ambient light sensor in low light. Not the crap we have in the P5.
The rest (more years of updates. Than just 3 years) is already confirmed. A smaller size would be nicer. But the P8 size seems good.
In general I like the P8. But I'm still enjoying the P5 so I'm not hurried.