Notwithstanding the superb work done by the Chinooks on HERRICK and elsewhere, there would definitely be merit in a larger SH design - not so much for troop moves, more for internal vehicles. The ability to carry vehicles such as Jackal and Vector internally, coupled with the ability to rapidly disembark them on landing, would have marked benefits on ops.
A typical small AFV (Jackal, Wiesel 2, etc) will be 4.5m - 5m long, around 2m wide and at least 2m high, and weigh 5-7 Tonnes. Thus to move one internally, and deploy it rapidly, would require both a larger aircraft cabin than the Chinook's and a greater max internal payload. A Mi-26 would fit the bill, but I just can't see it happening!