It really depends upon the type of CG being played (e.g. day long CG scenario periods, as opposed to shorter time periods). The likes are pretty much the same for all as the RePh usually offers the chance to redeploy forces, either majorly or in a limited fashion; Offers a degree of FOW about reinforcements to be employed in the next CG period (i.e. scenario); the possibility of going "Idle" or giving the initiative to your opponent even if only in a limited fashion; and the ability to "out-guess" your opponent on operational employment of your forces for the next "active" CG period. Dislikes may be the almost total lack of any attrition of forces during an "Idle" period (very improbable in actuality, even during periods of relative inactivity in a given sector); Major Terrain alterations such as Flame/Blaze spread to mention just one aspect (results in several House Rules to address this when longer CG time periods are in effect); Relative stability of the Front Line of Troops (FLOT) during an Idle period(s), when in actuality it was usual fashion in most instances to pull back slightly to relieve direct confrontation in most instances (the longer the period of idleness, the more pronounced the distance between antagonists usually became).
There may be more of of each, but these are the ones that come rapidly to mind.