Franchising seems to be the best growth strategy for mid-sized hotels. By franchising they will be able to latch onto other sound hotels and branch on their base by using their name. This is what the Holiday Inn Express did that I used to work at. It was relatively easy to convert bedding standards and uniforms to meet the franchising expectations and then guests knew they were getting a consistent stay when they made a reservation.
Large hotels growth strategy should be to secure additional management if they are struggling. If current management team is not showing profits than any additional help cannot hurt them get on their feet. Managing such a large hotel with so many extra amenities is stressful and should be done by a qualified individual. If there are management teams that specialize in this then I think large hotels should take advantage of what is available for the taking.