While you offered some very good points I feel your weighing out was mostly in favor of rotation during peek hours. Its easy to argue that during peak hours we should have a rotation because it limits the amount of time spent on popular maps and adds new elements to the consistent grind of popular maps.
Furthermore, this post took me so long to address because I had very little time in which to completely evaluate it.
Now while I do NOT play source, I can tailor my evaluation based on my point of view of map rotation on 1.6. So if you find any argument you take disagreement with then I’m sorry and I would hope you can post a better idea. Or at the minimum a supplement
When asking yourself the fundamental question of whether or not to use a rotation system what you have to ask is : to whom are you pandering, regulars or the general populace.
Since in this scenario this question is already answered for us ( regs. ) it is fair to continue with these points in mind:
1. Our regulars frequent the server on a daily basis
2. The amount of time played by the average regular player I would easily say between 1 hour to 3 hours.
3. The length of map rotation
4. Population of server during OFF peak hours.
Now we must as freeman did address the pros and cons
Mapvoting
Pros:
-Choice of next map — relative plus for most players
-Ensures a popular rotation and relatively high population
-If the appropriate restrictions are set there are a variety of maps played
Cons:
-If losing in the voting–resentment followed by flaming for being a crybaby 
-If inappropriate restrictions are in place map variety is minimized — ultimately hurtful towards regulars 
vs
Rotation
Pros:
-Consistent cycle that ensures map variety
-Allows players to “time” when they want to play
-No fuss and muss about losing voting
Cons:
-As far as freedom on the internet goes it becomes severely limited not to have a “voice” in which map you play
-Certain maps drastically reduce player population (or as I like to call it, the death spin)
-Most large maps suck without server population.
Again. This is not specific to EVERYDAY but it is fair to address some key points about each argument.
1 Rotation is absolutely the most responsible measure during peak hours for a variety of gaming
2 Rotation will guarantee map variety
3 Rotation will destroy all flexibility in the way maps are played
4 Rotation will assure that casual players avoid unpopular maps
If our goal is maximization of maps played during peak hours you have my total agreement.
However to specifically state that one is greater than another is simply not feasible. Drastic times call for drastic measure and I personally believe that during off peak hours. Between 2am EST – 2/3pm EST map rotation is detrimental to server population as well as regular gamers who actually enjoy dust2, office, aztec ( im only a fan of d2 the rest suck *edited*).
Thank you,
Erick
Ps will edit at a later time GF is yelling at me for typing at 1:30 am 