Definitely a larger hose size is indicated. One option that you have is to insert a 'Wye' close to the pump and add an additional 2" line. This will give you a flow rate similar to a 3" line and save you from having to tear out the existing line.
A 10,000 gph pump seems like overkill, IMO. 7,000-7,500 gph should provide more than sufficient flow. Any standard high efficiency submersible should significantly lower your power consumption.
"Everybody is ignorant, only on different subjects." - Will Rogers