– homogeneous means that the total power is homogeneously distributed over all RBs.
– You can assign different powers to different eNBs/femtocells. You have to write your own routine for this, which you can insert, e.g., in LTE_init_network_generation.
– yes, you can still alter the power levels after calculating the wideband-SINR, which mainly serves to determine the sector assignment.
– yes, it is possible to change the power levels during the scheduling process. You will have to implement this by yourself though.