I work with a VFR project which does something very similar, and even for VFR the cost of licensing the relavant data is quite high for the return. If you have to go to many third parties for all that data, then you have to be able to offset the costs somewhere to stay competitive. If you harvest and collate the data yourself, then your systems and procedures need to be absolutely watertight and fully certified.
Finding a stable middle ground between the two is the key to success. Good luck!