I have two guinea pigs and a big cage, but I feel like it's sorta small and want to build a loft for them. My cage is homemade and is not compatible with C&C. I need help with ideas for the loft and ramp. One of my guinea pigs refuses to go up super steep ramps, and the other one is way too fast, so sometimes he can crash into fences. I'm afraid that he might fall off and get hurt. What should I do?