The most important thing I like about this product its easy of use it has all you need for your project which includes shaders effects materials etc..
It's very fast even when using complex models with many thousands or more triangles per model! Also there are some great tutorials out their so if something doesn't work at first just keep trying until u get what ur looking fo rand then everything will be fine!! There isn;t anything really i don know how they could improve but maybe add an option where we can set our own vertex buffers instead off loading them from files? Maybe also have different types such as dynamic/static meshes (which would make sense since static mesh wont change after load). We used ogre mostly because other engines weren´nt good enough nor was free software available yet otherwise id probably go wth blender :).