The best ramp is Lake Havasu Marina located on the island. The problem currently with the marina is the new manager is a major A$$hole. They are restricting boats over 36' from launching at this time. We have started a boycott, along with several others, and have written letters to the owner who does not live in town.
The owners father, Richard mcCulloch (Same as the chainsaws) started the community for boaters, and to test his race boats on the lake. He may have not even know what is happening. We also have sent letters to various businesses and City officials regarding the situation. We will see what happens. The city exist because of boating, and the mayor owns a boat company.
There are other launch ramps on the lake, with Windsor beach being the one we use for our Top Gun now. It is located a few miles south of where the refuge is being built. The north ramp at windsor is ok for large boats, but it is not a protected ramp. In windy / choppy conditions it can be a problem.
I talked to the Nautical Inn, also located on the island, about using their ramp. They told me it is for their guest, but said we could probably work something out if we wanted to use it. it is not great but they do launch house boats there so it will work.
There are other public ramps, as well as private and state owned ramps on the lake but depending on the size of your boat they might or might not work for you.
I talked to the owner of Alco Marine this past weekend, and he said there are some local business owners that are trying to adress the launching issues. The protected area that surrounds the lake makes access a problem though.