I have an electric pump too, it is a naish, and I found out too that it struggles to get the full pressure. So what?
I am using the manual pump to inflate the struts, whilst the electric one is pumping the guts of the leading edge.
When I finish the struts, the leading edge is almost there, so 10-12 extra manual pumps in the leading edge and I am ready to go in about 5 minutes.
The fact that I do not push the pump to maximum pressure, helps with the life of the pump (alredy the second year, and the only think it is falling apart is the bag the pump seats in).
So, as you can see, I am only "half lazy bastard"