I actually like Sums more than my score or comments would suggest. Like you, I like the premise.
Oh, I figured you thought it was just average due to the review and score. Why didn't you keep the 3.5/5 rating? Just curious.
Also, I was reading your edit comments and truth be told, I'd totally have kept 'Seven Beer Snitch' over 'Kill Gil' (despite the fact that there'd be a lack of Christmas episodes in these Jean seasons, unless I'd just put 'Tis The Fifteenth Season' in there instead. Heck, I'd probably just do that). I'm probably one of few who really like that one ('Snitch') and find it underrated and the premise of Homer as a prison snitch pretty entertaining and fun, though I understand why some wouldn't like it so much (though even if I wouldn't be a big fan, I'm thinking I'd rather easily keep it over 'Kill Gil'. At least 'Snitch' has some excitement and likeability to it).