Boxsox; let me try to answer your questions, Minor league free agents normally are looking for two things, one is for an organization that will place them on their own 40 man roster, a Spring training ML invitation or a good opportunity to make the ML roster and the other one is an organization that offers the best financial deal. I really haven't spend much time this off season to find out who are the best minor league free agents are.
From the names that you mentioned Mike Restovich is by far the best prospect and one worthed to sign, in 2006 the 6-4 240 who will be 28 yrs in the early part of the new year hit for a 293 ave in AAA with 29 doubles and 27 HR, but 121 strike outs and 51 BB. You're correct Burnhan and Burkhardt are very similar players, non athletic, who's only tool that they can hit. Sorry but neither Butler, Meadows or Enrique Cruz does much for my interest.