It's not just the extra complexity. Will the relatively small speed gain that a wobbly prop and put away wheels gives you justify the (considerable) extra maintenance costs?
Regarding walking before running, I did my IMC, in a C150 and Twin Rating in a Twin Commanche over the same time period. The IMC rating left me feeling confident in IMC but although I felt confident in the Twin Comm, I had to work hard to think at 160 kts instaed of 85. It doesn't sound much of a difference but your nav happens twice as fast plus you anticipation time for radio calls etc is halved. It takes a bit of time and / or practice to get used to the change. If you can get in some intensive training and practice you'll probably find that it will all click quite quickly.