What these is the best model in my case

I'm traying to create a similar CORE XY but using cartesian normal modelfor having a system based on ramps (8bits) I can't create a real core xy I reached 2 possible models, and I would like you to evaluate which would be the best in this case- The first one is simpler but has the inherent inertia for moving the motor that has 300 grams together.- While in the second I tried to solve this problem after a lot of breaking my head.Attachment 14529Attachment 14528these models are not complete and many must be changed. The pictures are just paradise opinion on which one should I use.