AutoLaunch

Try sticking with these mineral lines: https://www.teamliquid.net/forum/sc2-maps/527886-proper-mineral-placement-lotv-edition They're used to maintain efficiency and standardization amongst all the maps.
A big reason for this is also to avoid cannon positions, which you map does have, seen here - https://i.imgur.com/UWyRkD3.jpg Fixing the mineral line and adjusting the space behind it (or moving the mineral line to have more than 2 spaces behind it) will avoid these.
Zerg can also not effectively wall off the natural with 3 evo chambers, as there isn't enough creep. Moving the mineral line forward one cell will fix this. https://i.imgur.com/bQ62ZXN.png
The map is incredibly narrow, armies are unlikely going to be able to engage eachother in any favorable situation. Due to the base count and space requirements of 4p maps, its advised they be slightly larger than normal, such as 150-160.
There is a major problem with any four player map, and that certain spawn positions will favor specific races in a given matchup. In your map, imagine a Zerg player spawning BR, and a Terran player spawning TR. The Terran has a must easier time harassing the Zerg, because the Zerg will expand away from their opponent, making it hard for them to defend their bases effectively, with less effort from the Terran. On the other hand, if it was Zerg TL and Terran TR, this is a bit more defensible. This is effectively the reason 4 player maps are avoided, so this map might be best saved for a future time.