We were on the Encore in November 2022 in an aft Haven Suite. This is before my wife's knee replacement. Though she had trouble walking it only took 4 minutes and 30 seconds to get to the bar in the Haven. Though there is a mental barrier to not being 'in the Haven', the truth is the aft suites aren't that far removed.(In full disclosure, when we had a Courtyard Penthouse suite it was on 19 seconds to the bar.)
The aft suite is huge and the 3rd traveler will have more than enough room. The bathroom is tight, though functional.
The balcony is humongous. We had two tables, 4 chairs and 2 loungers. More than enough room for three and the grand aft view from the ship.
I would personally go with the aft suite and put up with the minor inconvenience to get to the Haven.