Ubiquiti setup or mesh wifi

Hello, I currently have a 2 story house with fiber 1GB. Currently have a zen WiFi mesh system. The fiber is on the bottom floor connected to the first node and the second node is on the second floor of the house. It's about 2500sqft total. While we don't really have any issues with network interference or speeds and I work from home while also have a decent gaming rig along with smart TV's, appliances, etc. With no issues.

That being said, I've heard mesh is good but the unifi/ubiquiti could be better with less loss of speeds along with more control. So I'm looking into going that route but have no idea where to start.

My WFH office is on the second floor right above the room where the fiber comes into the house. I've noticed some wifi bars kinda drop periodically around the house but nothing major. Also, our house was built in 2023 but no Ethernet runs are through the house. I've never personally ran them either.

I guess my major question is, where would you start with this issue for a unifi/ubiquiti setup? I don't reallynwant to run ethernet through the house nor spend that type of money to do so and I know that's the better way but I was hoping there was a step down but still above what I have now, and that may rule out ubiquiti all together as it seems like most of that stuff is PoE but I could be mistaken and I'm pretty new at this.

Any information/tips or products recommended would be greatly appreciated!