optimizing load scene

am working on a racer game and i use subtance for the cars texture the problem is that game crashs on some devices when loading some scenes in the game, ive looked in this devices and most of them have mali as a gpu or older version of adreno like 304, when i tried to reduce the texture resolution it worked but its still not stable beside textures are really pixelated, is there any thing to do to optimize the scene load, here is a snap shot from the profiler when the scene load