upgrade from UB5 card to mikrotik N card using single chain

I need to update the cards (UB5), I need your recommendation to select best N mikrotik card that can be used in simple polarity (single chain) and the best way to connect that chain to use and which left unconnected.

antenas are 5ghz panes 90°, routerboard 433

now use 10mhz channels A rates, using N cards in 10mhz channel can negotiate N rates?

Please, someone tested the Mikrotik N cards using 1 pitail (1 chain) 10MHz only can help me decide which model would be better to replace ub5?

I already I have tried and it worked fine.
how much traffic you want to spend?

which model do you recommend? R52Hn or R52nM?

connect only chain 0? or 1?

now UB5 at 5ghz A 10mhz channel width, delivers up to 8 / 9 Mbits smoothly, with 45 clients connected
9.5/10.5mbits ping times go from 3 ms to 150ms

my 80% cpe can use N rates,

I want to deliver at least 15-20 megabits per panel, maintaining a 2-5ms ping, using 10MHz channels