partial wds

Hi,

I have a setup consisting of 3 routers. I’m trying to set up a wds network, but i’m having some problems on one of the routers.

Main router is RB2011 and is connected to the internet.
Second router is a Mikrotik hap lite, that is connected to the first via WDS. It works perfectly.
Third router(also hap lite) is too far from the other two for a stable wireless network. It has practically non existent signal to the main router(i can see the network, but can’t connect to it), and weak signal to the hap lite. It is connected to the main router via lan cable. Is there any way to have wds on it, but have it communicate via lan?
Currently if i enable wds, it constatly switches between wireless and wired network, and my data connection drops out every minute or so.
I’d like to have a single ssid across entire network, but if i just set the same ssid and put the third router in ap bridge, it doesnt want to switch to the router with a better signal. Currently i’m forced to run a different ssid on router 3 and manually switching between networks on my devices. If im between rooms, i still have signal to ssid 3, but the network is very unstable.

So, is there any way to get wds with 3 routers, but force the connection between two of them to go via ethernet cable?
Alternatively, is there any way to force devices to switch to a better signal automatically?