vh 20 - normally, sleeving or liners are used to repair a barrel set that thas become too thin in one or more places. In the case of repair for thin spots, the repaired wall thicknesses will for sure be greater than before the repair. How much greater depends on how thin before the repair and how thick after - metal is added. Metal added to the barels will always increase the gun's weight, move the balance point forward, and increase the MOI. In times past, some sleeving jobs done on the cheap had "excessively" thick barrels when finished and had fairly significent changes to handling. The owner of a gun with thin barrels must accept that there will be handling changes if the barrels are to be repaired. On the other hand, it is entirely possible to determine how much the handling will change and to control the change to some minimum amount.
B - stock dimensions, weight, balance point, and MOI are all quantative measurements - there is an exact number for each of these characteristics for each gun. Quantative characteristics are not "good" or "bad," they are simple facts about the gun. Interpertation of them as "good or "bad" is a personal issue for individual shooters to decide for themselves. For me personally, I think of a 14" LOP as "bad" because I need 15 3/4". Smaller people think of my long LOP guns as "bad" because they either struggle to shoot them or would have to have them shortened. Same of weight, balance, and MOI. I prefer guns that weigh around 7 1/4#, balance about 3 3/4" in front of the front trigger, and have a MOI of about 1.8. A fellow shooter likes 6# 10 oz, 4 5/8" balance, and 1.6. Neither of our guns are "good" of "bad" for handling, only different. Trying to associate "good" handling with a given maker is like saying that maker made only perfectly sized stocks. MOI, when measured, is a fact about the gun, just as are weight and balance point.