I have Zeiss 6-24x56 scopes for both my stalking rifles plus an Alpex 4K that spends more time on one of them than the Zeiss does.
The 56mm objective allows more light into the scope to start with, however optimum exit pupil size is 7mm meaning optimum magnification is 8x (56 / 7). Most of the time the scope stays at 8x, although gets out down to 6x sometimes when in the woods on foot. In daylight in a highseat the mag sits at 8x unless I need a bit more when it usually goes up to around 12x. On very rare occasions it’ll get wound up to 24x but only when I have, for example, a fallow out in the middle of a field that I can lift my head & watch after the shot.
The Alpex sits at 7x normally as this gives me a good compromise of field of view & also allows use of the LRF box. In some circumstances, such as yesterdays Muntjac buck, it gets turned up a notch to 14x to enable more accurate shot placement.
As already been said, a 8x56 scope is usually more than enough for UK stalking & if you’re predominantly in woodland in foot then a 6x42 should do you fine.