My experience with the XTZ is limited, but it is pretty much standard practice to drop the forks in the yokes by the same amount you lower the rear. This maintains the bike's balance fore/aft, although it will probably mean you will have to shorten the sidestand again. That should gain you a bit more 'lowness'.
When lowering the forks, it is best to do it with the wheel out and the bike supported under the engine. That way you can deal with each fork leg separately. It is a
bad idea to loosen off the fork clamps with the weight on the front wheel, as the bike will drop as far as it can (much further than you need) and you will have the devil's own job getting it up again. I haven't done this, obviously, but a friend of a friend told me ...
