ASLR is no way to prevent such cheats. First, ASLR can be disabled system-wide from registry, or on process-basis by launching the executable in XP compatibility mode.

Second point is that the cheating tools(check cheat engine forums) and malware targeting specific executables have successfully worked around ASLR.

Since you are working on an online game, you should rely on values stored on the server and not trust the client.