yes I tried to change CELLRESHYST on the LAC border. In some cases SDCCH traffic could go down by 50% (to avoid ping-pong LAC updates). In some caseses it is good solution to move one sector from one LAC to neighbouring LAC (in case of same MSC).
We have NBLKACGR = 1 for all cells as default. Durig Christmas day No of paging increase 2times (in some areas 2.5 up to 3 times). We had ACGR owerload and paging succesful rate goes down (one TRX cell with COMBINED configuration).