After just about completing and Arms Race game I have to say it was one of the best maps ever. Interesting points;
1.) Early Resource Deficiency (Food & Manpower) is a n00b trap. I dunno how many exactly positions, it was certainly a half dozen or more, made the mistake of building extra barracks to fix the Manpower issue, but only ended up getting themselves suckered into a Negative Food Death Spiral. I did well because I always upgrade my resources, and in this Round I paid super-close attention to Food. You might try including a warning about this in future Arms Race-style Rounds.
2.) A.I. Bots were mean. Really mean. I suffered some of my heaviest losses early on when I underestimated a neighboring AI Bot and took heavier losses than anticipated. I compensated for the loss, but I noticed many players had this problem - and Lord Have Pity on the players that attacked an Inactive player nation that had not yet fought any battles! However, after that first conflict, I easily adapted, and used my new knowledge successfully. Again, maybe you can be apply a little more emphasis on how potent the AI Bots are in these kinds of Rounds.
3.) Artillery and Railguns actually were useful for me for a change. Early on, anyway; after I expanded my economy sufficiently I left the artillery largely behind and went back to TAC Spam, but I did appreciate how this Round made units I almost never use become important, or at least, significant.
4.) I gained a new appreciation for Commandos, and Mechanized/Motorized Infantry. I never use these units in regular games. Probably still won't as I hate building L2 & L3 Barracks so I only get Commandos when I happen to park my capital on a captured enemy province with a L2 Barracks, but in this game they were worthwhile.
5.) Rockets Are King in this Round; rockets are always handy, but when your opponent has a 30+ stack with good AA defense, has artillery that out ranges yours, and plenty of 'meat' in the form of infantry or armor, rockets give a huge advantage. As stated, this is usually the case, but rarely in a game is there so many L5 forts so close together across so wide a landscape. In addition, having so many L3 Airbases in close proximity enhanced the ability to Rocket Spam as needed, so it was a strange experience, but one I enjoyed.
6.) Blitzes were only possible if your opponent did not have sufficient forces to defend those forts, so LTs (my fave armor unit) was actually not as effective as MECH or even my MOT units. In most games this is not the case at all; I have taken almost all of North America or Africa in past games with only a dozen or so LTs and a crap ton of air' in this game that combo was not always enough, and when it was I could easily be delayed by even a moderately defended fortified city. I appreciated the change.
7.) x2 Speed Rocks. I did not care much for x4 Speed; I have a very active playing style and x4 required much to high a temporal commitment; but x2 is just about perfect.
8.) Mistakes were punished more severely; whether is the enhanced speed, the more aggressive AI, or the resource issues at the beginning, I noticed that players that made errors were punished very quickly and harshly. Especially if they were not active enough to identify and correct the mistakes they made. Some n00bs got overwhelmed and never expanded beyond a couple of provinces or else were overrun by the AI, or starved themselves into morale oblivion. If any Round needs a 'Rank Minimum' it is the Arms Race Rounds.
9.) TAC Spam could actually be hindered, though not stopped. In most games I start TAC Spam and just run over position after position after position until I literally have to stop because I have expanded myself into a serious negative Food situation (whereupon I pause and develop my Food production until it is a positive modifier again). In this game I had to be much more careful as an enemy could spam AAGs and SPAAGs and park the darn things in a fort (usually a L3 - L5) somewhere close by and make things painful for your air force. Fortunately for me, by the time my opponents started spamming AAGs and SPAAGs I already had an overwhelmingly powerful air force and a dominate economy so I would not care too much if I traded a TAC for an AAG (something I would never be happy about in most cases), but it was cool to always have that additional threat when I was slinging my bombers across the battlefield.
10.) Alliances become more valuable. Because it could take so much more energy to KO a position, making alliances, however temporary, becomes very profitable. In a recent 100p I didn't bother allying with anyone until only about 9 players remained because I simply didn't need to; I TAC-Spammed my way to a huge territorial advantage quite quickly and never had to worry about anything. In this game, even when I was clearly ahead, I had to consider which positions I was going to attack with care; if they were largely untouched by war and controlled a cramped position I usually avoided attacking them until I knew I had overwhelming firepower and no other enemies to worry about. In fact, I lost the most TAC right at the end of the match when I parked 82 air units (about 60 TAC) over a L5 Fort with 11 AAGs mixed in a 35 unit stack. I lost over 60 air units in that one battle (not sure exactly how many TAC, but I only had 2 INT & 11 TAC when the fight was over); thus justifying my earlier caution when dealing with potential targets.
11.) Intel Gathering is super-important. Because of the aforementioned issues, knowing where your target's units are and what they were doing is paramount. I am a heavy spy user, but in this game I think they are as mandatory as artillery if you intend on doing anything other than just hanging out in your forts.
12.) Just remembered; Elite ART, Elite SPART, Elite TAC, Elite INT, Elite INF, Elite MOT, Elite MECH, and Elite MT's were all super useful on this map. The ART & SPART have +10km range over non elites, which really mattered alot. Sadly, I did not have any of these while several of my enemies did, and it really does take away your options. I did have Elite INF & TAC, and got full use out of both and was very pleased; however Elite MOT & Elite Mech would have been even more powerful (and the normal versions are, in fact, superior to the Elite INF). Elite MTs can move faster than non-elite LTs, and really added to the hitting power of my opponent's stacks (though my complete control of the air nullified that edge, if we had been closer in air power it would have been a strong advantage for my foes).
In closing, the Arms Race was awesome. Please add these games to your regular lineup; it is the best and most enjoyable I have ever played. It was the same, but different, and different in a very good way!
Keep up the Good Work!