The change to the cleric's channel energy ability of only your charisma bonus in my opinion really screws up the cleric.
First 22/32 cleric feats revolve around the channel/heal/harm mechanic and expanding the way it interacts. Channel is set up to do far more than heal or harm undead with feats and the cleric is losing one of their most versatile assets.
Secondly it turns Cha into a primary stat along with Wis (before a cleric build could focus on other stats or Cha based on your build concept of the cleric as they always had a base ability of at least 3 to channel their deity’s energy type. Now without the base 3 and the focus solely on Cha you may have literally no ability to even channel your given deity).
Third, it forces any heal/harm cleric or undead slayer/ control build to require a supplemental magical item to work (I thought the point was to make magic items less of a necessity) or they are going to lose depth in their ability to function in a more versatile way as they are forced to fill up already meager spell per day caps with heal/ harm spells to make up for the difference (I was already filling a heightened slot with a heal spell even with 3+Cha (even with a 16 Cha giving me 6 total channels per day (now 3) a party can blow through them during a dungeon crawl).
Fourth, this really hurts any party that does not have another heal class in their mix as the stated intent was to not make the cleric as good at healing so other classes would pick up the slack (that’s making a mighty big assumption you have other heal classes in the party or is going to force building parties that way, again taking out choices).
Fifth, the cleric lost ability but it wasn't given anything in its place or another solid route of feat focus like other classes have so they only became less viable as a class. (sorry for the rant)
Fun Fact: I now have a domain spell power that effects channel (undead's bane) that I can use more times than I can actually channel, lol