I believe if the LAN Server is not improved NA will hurt in the Long Run
Now I know from a Business Perspective why the LAN server is not as optimized as it could be: LAN just doesn't generate as much revenue to justify it (smaller player base and online transactions in the region are not as common both because of disposable income available and cultural factors). This makes sense from that angle and I'm not here to complain about it because the server IS playable and in way better state than a free to play game ought to.
However! The base ping for LAN was recently upped from 60 to 75 in Mexico City (where the majority of LAN players reside). Now I started leveling my NA account (this one) and the ping only goes up from 75 to 90 (I have a 50 up and down megabits optic fiber connection). On top of that, my connection is way more stable in NA (LAN for some reason gets lag spikes in the afternoon). That is without taking into account that Americans and Canadians have way better internet connections than Mexicans and Colombians in general (Colombian's connection usually suck because they are so far away from the server).
All this being said, I'm now wondering at this point why not make my NA account my main: I get better quality matches because the connection is more stable, everyone else connection is better so there are not nearly as many AFKs and because the player base in this region is larger I get to have more competitive matches because the match making works better with more players.
THE PROBLEM: If more Mexican players start thinking like I do, the NA quality of matches will become worst because you will have people on the server that do not speak English (so they can't communicate with their team mates), disconnect more frequently and have poorer internet connections.
TL;DR : If the NA and LAN servers give you almost the same ping, people from LAN may start flocking to NA, which will worsen the quality of NA matches (Reason's described in post).