Comparison of Barbarians in Civ V and Civ IV:
For the record, Barbarians being optional for HOF has been the traditional approach. (i.e. civ3 and civ4) Civ5 has a different approach to barbarians that seem more central to game play. We are leaning toward making barbs being require for HOF submissions. The poll is intended to spark discussion and validate our thinking.
How are Barbarians more central to game play in Civ V than in Civ IV? The Civ V just adds some bells and whistles to Barbarians while making them much weaker in many ways ...
Civ V) You get 25 wealth for destroying a Barbarian Encampment.
Civ IV) You get a fully functional city for capturing a Barbarian City plus maybe some wealth too depending on options specified.
Civ V) You get influence with a City State when you destroy a Barbarian Encampment they specify.
Civ IV) Options permitting, you get a fully functional "City State" plus some wealth when capturing
any Barbarian City.
Civ V) Otto von Bismarck: Furor Teutonicus: Upon defeating a Barbarian unit inside an encampment, there is a 50% chance you earn 25 Gold and they join your side.
Civ V) Suleiman Kanuni: Barbary Corsairs: 50% Chance of converting a Barbarian naval unit to your side and earning 25 Gold.
Civ V) Askia Muhammad I: River Warlord: Receive triple Gold from Barbarian encampments and pillaging Cities. Embarked units can defend themselves.
These three are the only Leaders that have a Unique Ability whose power increases with the number of Barbarian Encampments found. Since this affects a small minority of Leaders, it is hardly central to game play.
Civ IV) All Leaders in Civ IV are able to more easily kill Barbarian units and capture Barbarian Cities.
Civ V) Barbarian spawn rate seems far slower.
Civ IV) Barbarian spawn rate seems much faster.
In conclusion, Barbarians in Civ IV are far more central to game play in Civ IV than in Civ V.
Is this or is this not the type of discussion you want to see concerning whether or not to allow the "No Barbarian" option in the Civ V HoF?
Random Opponents:
The thought that all oppenents should be random seems like an idea worth considering. The use of cherry-picked opponents haa not gone unnoticed as some of the gauntlets show. People are going to toss out games for many reasons in their quest for perfect games. The question is would the time required to find a good mix of opponents be low enough to provide a significant advantage to players with more time? On some map types it could be a fairly large investment of time.
Before the Game Start is generated, all the Opponents can be specified as Random, but after the generation is done and before the first move in Turn 0, all teams have been resolved to specific opponents. People are simply going to toss out games whose "Random Opponents" they don't like, so the opponents are no longer statically random. A player can start a game a thousand times to get the opponents he wants. Do we want players who can win the Random Opponent lottery to win the #1 games as opposed to the best players?
As I stated in a recent post, there is no way to ensure that Opponents are Random without forcing every game started to be completed. Why? Simply because players will have a new huge category of abandoned games whose opponents they didn't like enough. Like you said "People are going to toss out games for many reasons in their quest for perfect games.", why add to it by forcing "Random Opponents" which become statistically skewed by player abandonment anyway?
The only way Random Opponents works is when everyone gets the same of "Random Opponents" as in a "Game of the Month". Random Opponents works in a GOTM, because you get exactly one chance to play a game and for that one chance the opponents are not known to you until you contact them. Suppose we want to give GOTM players a second chance to play in the same competition. To be fair, one must use the same set of initially random opponents, but in the second game, the player knows who all the opponents will be. The HoF provides multiple chances to submit and this compounds the Random Opponent problem further.
If we want the HoF to be a measure of randomness (as opposed to skill), then by means include Random Opponents. On the other hand, if we want the HoF to be a measure of player skill, then we must eliminate as much randomness as possible, except that which is required in excellent game design to meaningfully challenge the player's risk assessment skills.
Civ V HoF Presentation Structure:
[teaser]
BTW, the Civ5 HOF is going to have tables defined by the combination of Victory Condition, Difficulty, Map Size, Speed, Map Type and Leader. The tables lists will be sorted by participation to minimize the effect of empty/unpopular tables (i.e. Huge, Marathon, Deity, Time, etc.

).
[/teaser]
Doesn't the Ad Hoc search page provide almost exactly same sorting parameters and control over them as you stated above? Doesn't Civ V have a "Start Era"?
Won't the Civ V HoF Table be rather sparse when specifying some specific Leader and specific "Map Type" (not to be confused with "Map Size") to the traditional categories of Victory Condition, Difficulty, Map Size, and Speed?
Sun Tzu Wu