There is another possible choice to consider:
Get some filter material (i.e. Pad) or a sponge filter and put it into an existing tank while you are deciding when and what kind of fish you are going to be doing. Once you have decided, take this material and place it in the new tank. If it's been in the other tank for a while, it should have enough starting bacteria for an instant cycle. I would use whatever tank you have the most amount of fish in to do this as more fish equals more bacteria necessary to keep the water parameters in check equals a healthier bed.
Keep in mind tho, as indicated previously, if the tank gets sick, you will be transferring the disease into the new tank. If this is parasitic, it can be remedied by not having any fish in the tank and the parasite will die off. If it it bacterial or fungal, it would not be advisable to transfer the material.
FYI: I seeded an entire warehouse using this method. 1 roll of DLS material from the old system seeding 25,000 gals of new water.
Just something to think about