Low time Multi
You have gotten some good advice here regarding the issues of a low time PPL in a multi. I got my PPL in 1969, instrument in 1977 and multi in 1981. It was marginal in 1981 to be allowed to fly the twin after getting your multi rating because of insurance issues. I think they required 500 hours total time and the rating from the same flight school (FBO) that rented out the aricraft. Over the years, I kept enough multi time to just stay ahead of the increasing insurance requirements to allow me to rent.
We bought our Duchess this past year (first multi engine we have owned, but not first aircraft). The first year insurance was pretty high given I had no time in "make and model", even though I had 900 TT and over 100 multi. They did require 5 hours make and model (dual) before solo or passengers.
During the last year I got my commercial SEL (while the Duchess was spending time in the shop getting things fixed and upgraded) and also did my commercial MEL in the Duchess. My insurance dropped 30% going into year two. That is with the additional ratings and 150 hours make and model now. I'm told that another benchmark is 250 hours make and model....will find out next year perhaps.
I would be surprised if anyone can provide a twin for you at your experience level at a rate that will beat the airlines. Anything can be insured, but you should not assume that the act of "renting" an aircraft covers insurance issues. As you progress to more advanced aircraft, you will have those discussions with any FBO you use.
Also, you said you need a twin to fly family and baggage. There are many singles that will easily carry as much or more than our Duchess (a typical 4 seat twin), and for far less money. If you need six seats and baggage, you might think in terms of a Cherokee 6, however, I bet that you might not even meet the minimum time required to rent one of those with 57 hours TT.
Nothing wrong with getting your multi rating prior to your instrument, but I think getting the instrument first is better, and will be more usefull. The multi rating is not particularly difficult to get, and getting it does not necessarily improve your overall flying skills anywhere close to what an instrument rating provides. Also, insurance companies might consider it odd that you would have the multi rating without an instrument ticket.
Good luck and have fun. Let us know what the FBO's you visit have to say about the requirements.