Improving my Wifi - move to Mesh or improve my ASUS setup?

[Livin]

My Goals:
-- No dead spots in the entire 3-level 4000sqft living space & 3 car garage: currently fine, no dead spots and strong signals
-- 5 family wifi devices (phones/tab) and a few guest wifi devices
-- String coverage of front and back yards; longer distance, stronger signal
- today signal goes about 50' out front and very weak, back yard is better but larger so coverage is not good enough yet

Current System:
Three ASUS AC68U w/ wired backhaul through my HPE router.
- One in the room closest the front yard / front door (AP mode - HGG FW)
- One nearly dead center of the house in the kitchen (AP mode - Merlin 3.0.0.4.380_7743 FW)
- One in the walk-out basement near the back yard (Router mode - HGG FW)
-- SSIDs are all different on all APs & bands
... 56-60 total wired & wifi devices at any given time

Questions:

1. Would changing to Ubiquity AP (or other recommended AP to use with the ASUS?) at the front or back provide a longer reach?
... and what would I need/want to do it?

2. With Ubiquity or Orbi Does the 'hand-off' really work seamlessly , and better, than using the 3 ASUS?

3. I have a strong signal in most places in the home from at least 2 of the ASUS APs... for better hand-off, should I use the same or different SSIDs?

4. Anything else I should consider or be asking?

thx for the advice!

 

[System Error Message]

ubiquiti is decent as a basic AP, good signal but your clients must also keep up as far as signal strength goes. I have my asus router set up to improve battery life too.
SSIDs can be the same for automatic hand off but in the case of confusions. Ubiquiti does not do mesh.

Measure where your dead spots are. You already have 3 asus routers and i wouldnt bother worrying about open space coverage so you dont have to position them near the yards.

You have 3 wifi APs, you dont need one in the center, for better coverage just move them around instead to cover the weaker spots. Open space is easy in coverage so focus areas that have many walls in between the area you want to cover, imagine arranging 3 in 3D to cover as much area as possible.

Dont bother upping your tx power much. for 2.4Ghz theres so much interference so tweak it, for 5Ghz you can max out tx power.

With orbi you will get better handoff for seamless roaming, but orbi focuses on being plentiful rather a router like asus or ubiquiti focuses on a single powerful AP.