It's getting a little late, but statistics exams be damned!
I was reading Sims's resignation thread, which derailed into general commentary on the rules, and so I decided to formulate my thoughts and post 'em here...
Map absolutely shouldn't be random. Here's why:
Some map combos, like the previously mentioned Incans + Mesa/Himalayans, are nearly impossible to be defeated. How can a nation that receives massive economic bonuses from mining and is protected from raiding by the constricted map be beat? It takes a very large difference in skill to overcome that, one that cannot be found between most good players.
Some maps are broken. For instance, after going undefeated against a certain player, we drew Great Lakes in a 1v1. There were rougly 10-11 fish in reach of his cities, compared to an empty lake and a lake with 1 fish on mine. Needless to say, I had no chance. Great Lakes isn't always like that, but it can be.
Some maps require different strategies: for instance, Amazon Rainforest has many more ruins than most land maps. A scouting-heavy start with Iroquois, Spanish, Chinese, or even Lakota can easily be successful there, but it would have little chance on the more ruin-scarce Australian Outback. But you cannot select your nation in anticipation of that with random maps...
Basically, just like random nations can screw a match up with a bad mis-match, so can random maps. My proposed solution? Just assign every territory a map. E.G, The Andes and the Himalayas could both be himalayans, Ethiopian Highlands could be mesa, Indonesia could be East Indies, etc. This way, the tourney could represent all the RoN maps, and because the players know the map in advance, they can plan and pick nations accordingly.
Secondly, the small map size is too big. Although it's not a good reason per se, the preferred 1v1 size of the community is arena. (Also in most tournaments too) So, most of the good players, who, after the opening rounds, will still be playing, will have plenty of experience with arena play, but not small. Why not go with them? Make it arena, and hopefully the quality/level of play will go up correspondingly.
Now, this is just my experience, and is all huge generalizations...
Arena sized play on land maps is usually a fast 1-1-1-1, 0-1-1-1, or 1-1-1-2 tech start in most circumstances leading up to a fast classical era. From there, lots of raiding with cavalry and incursions/ambushes with the smallish armies of the time goes back and forth between both players. The game is often decided then (nearly as often though, one player hits medieval early and the large cities postpone the critical city battles), but a few more ages will typically be seen as one player goes for the finish. It's a high intensity, high combat situation that starts pretty early on.
Small sized play, although I don't have nearly as much experience with it, has so far, seen early fighting much diminished in importance, because of the large distance between the two playeres. Even if you can obtain a military advantage early, often reinforcements take so long to arrive that nothing can be held. Placing the third city is much easier because of the extra resources on the map, and usually happens before any major battles. Often large-scale fighting doesn't start until the medieval age. Basically, it's like arena, but there's an extra 2-5 minutes before decisive combat occurs.
Finally, when there's an imbalance of rare resources, nation/map combos, they can often still be overcome with fast, early raiding that attempts to shut down the economy of the other nation before their advantages accumulate. On a small map, raiders will arrive 20-40 seconds later, giving economic players a better chance to defend their advantages, exacerbating the imblanace. While that's not neccessarily a bad thing, it's not what most players are accustomed to...
So, in conclusion, arena sized map with assigned maps per territory.