As a WeMod staff member, I definitely can’t mention any other rival services.
That would be like a Pepsi employee telling everyone to buy Coke. 
You’re likely to experience the exact same thing with other trainer services. If the game uses exactly all of your 4gb of RAM, even a trainer that uses a very small amount of that RAM will still cause issues for you, because the entire 4gb is taken by the game.
The two best solutions are:
- Upgrade your RAM.
- Play a less taxing game: A list of games for your low-spec potato computer.