but very keen to get back into the sportgliding and obvious benefits, combined with the limited touring capability
You will find that its the reverse in fact! The Grob 109B has a very limited gliding capability but an exceptional touring ability. Gliding wise you need an extremey good UK day. You will not be able to penetrate into wind!
Cruise speed is a around 90Knots with an endurance in the region of 6 hours.
There is a lot of room for baggage, although at first glance you wouldnt think it.
There are weight issues. See the Flight manual for details.
6ft 5 may be a problem Try one on first.