If an iPhone 8 does everything you need, why change? But it is an A11/2GB platform, so 3 years old in 2020. At some point you might want an upgrade.
So one option will be the “SE2”, an upgraded iPhone 8. With A13/3GB innards, it should be good until 2025.
Another option will be the 5.4” iPhone 12. It will A14/3GB (or maybe 4GB), have a couple rear cameras, FaceID, OLED for somewhere $599-699. It will be slightly smaller in width and height than iPhone 8, though thicker. This one will reportedly have 5G, but possibly not the mmWave frequencies (the ones that don’t penetrate walls) that are meant for high density urban areas and fixed wireless access.
You can just pass on the “SE2” in March and wait for the iPhone 12 in the fall. If it’s too expensive for what you get, check out the “SE2”. It’s said to sell for $399. Maybe one of those will appeal to you, or both—or neither. Hard to say at this point.
iPhone 12 - 5.4”
A14
4 GB RAM
Dual or Triple cameras
OLED
5G based on country. But same as Pro.
Face ID
Base model will probably be $749-799 or so.