I'll flat out admit that I'm a powergamer but I don't go all out; I'm more than willing to choose a few "not as good" feats or powers if they fit my character concept, and not choose very good things because I don't like how their flavor is in regards to how I envision my character.
This is pretty much where I am as well. My Avenger, for instance, didn't choose Tempus as his deity in LFR, despite the fact that Righteous Wrath of Tempus is clearly the best Channel Divinity feat. I have a number of my friends who harp on me for that. But I wanted an Avenger that was Lawful Good and was a protector of innocents and justice. So I picked Torm. Even though the feat that goes with Torm isn't very good.
However, that character has an 18 Wis and 18 Int. I don't like my chances to hit if I have less than an 18 in my primary stat. It is frustrating how often I miss with an 18 in my prime stat and a +2 proficiency weapon. I'm certainly not going to decrease that any further.
That's outright inexcusable, in my opinion. I can forgive choosing some inferior choices based on flavor reasons, since not everybody plays the WAAC (win at all costs) mentality, but if you wrote the fraking game then you should know the fraking rules. How many WotC articles have we seen that give outright illegal and/or wrong advice in the context of the rules?
There's a couple of reasons for this. There is a tinkerer's culture in R&D and WOTC in general. They are employed as game designers. They are used to coming up with new rules all of the time. They aren't used to consulting a book to see what the actual rule is.
Unlike the rest of us who wait for a book to be released and then consult it a couple of times to make sure we have it correct, they are used to going through 5 or 6 iterations of the same rule. Often they change the rule every session in order to try something new.
Plus, a lot of the rules were designed in committee. Two or three different designers may have wrote different rules for the same thing. They get together, discuss the good and bad points of each and decide on the one they are going to use. Not everyone agrees. Some of the designers keep using their own version of the rule in their home games.
Unlike some of us who may get on message boards and complain that a certain rule doesn't work well, they just change a rule as soon as they don't like it in their own home games.
I sometimes think that it might be better for the game if all the designers were forced to play or run at least one game on a regular basis that was nothing but the published rules with no house rules or development rules. But, their time is probably better spent testing stuff that isn't out yet.