We have a small Achilles RIB (less than 9') that we almost always tow. The only times we carry it on deck is extended sails in the ocean, like crossing to the Bahamas. Towing slows us a little, usually less than a ½ kt.
The problem with foredeck storage is visibility. The dinghy will reduce visibility forward, which is not a big issue 50 miles off shore, it is a problem on the Elizabeth River in Norfolk (don't ask).
It is best to not tow the dinghy for any distance with the motor on the dinghy. It puts the motor at risk if the dinghy should flip and adds weight to the tow which slows you even more. Do get a crane to store the motor on the pushpit. I have used both a Novalift and a Garhauer lift, far and away I prefer the Garhauer as the motor can be easily raised by one person in the dinghy.