A "power back" that's only good for short yardage situations seems like a limited usage of a roster spot. Blount was never one anyway, neither was Ridley. Devlin is coming back too.They still need a power back, i.e. someone good on 3rd and 4th and 1 or 2. I'd be inclined to package White to upgrade Blount. I love Forte, but he's not really a power back.
A top 10 RB in 2015 earned about $4m (Vereen, Spiller, Ingram, etc.) If Forte is serious about what he was saying about salary vs. SBs, then a 3-year, $12m deal with a 2-year guarantee with $7m-$8m range (most RB contracts are guaranteed for 40% or less) would not only be the best offensive upgrade this team can make in FA, but also very doable under the cap.
Forte is a dual thread, once-elite, now SB-hungry veteran with gas left in the tank, and (by all accounts) a locker room leader. This guy fits the type of pickup BB does and should be terrific as a Patriot.
Edit: also encouraging -- had his best games after coming back from the MCL sprain in week 12.