(These are all based on my own experiences. We may have different outcomes after the update.)
Heating issues - It seems like the heating issues on my A32 4g were fixed after upgrading to One UI 5. Idk but the One UI 4.1 update was causing my phone to heat up. Good thing it's fixed now.
Battery performance - I don't think if it became worse nor it became better, tbh. I'll wait again for a few more days.
Overall smoothness - current UI is smoother than the previous one.
