I think such a solution is much better than any builtin winch.
There are Portable Winches arround, with a weight of 11kg, who are capable to handle a 5to.
My Warn 9.5 XP & Frontbar are arround 80kg - and i cant winch to the rear. Probably you have to use a snatch block more often with a chainsaw based solution - but yes - you have too a chainsaw.
When i had to rebuilt my setup - i would go with a portable winch.
Here i had loved to be able to winch to the rear:
I dont know, that this passage is so deep there. It was not visible. To winch to the front was not a good idea, because there are much deeper areas, a buddy told me.
Good to spent the day not alone, right?
We will cross africa alone - and i would be happy if i had such a portable, in my rear.
But we will be a bit over the legal weight, together with 85l Water and 180l additional fuel and all stuff - and there is no free space for a Lewis or capable Handwinch, who are able to handle 3.5to.
We have shovels, Maxtrax, Winch, ground anchor - and hope that this will be enough
If you dont have allready a winch and have an overlanding using purpose - go with a portable! For more hardcore stuff, you should consider a builtin winch, and a portable ;-)
Surfy