I think the Harlequin transfer is a nice opportunity for some changes
in ME PBM. It is a fine game, and I suspect that there are a lot of
ideas floating around in the community. From a practical perspective,
anything involving coding changes is likely to be slow. The easiest
thing to alter is the setup process.
I would recommend that some of the nations not be available to
first-time and novice players. These fall into two groups: positions
that are likely to be very frustrating for first-timers and positions
that are crucial to the respective teams. For the first class, I
think that a completed game would be needed to take the position; for
the second class, perhaps six months of play so that the players would
at least have a good working grasp of game mechanics. In addition, I
think that on the intro page Harlequin should recommend against
(although not prohibit) neutrals for a first game. Mentoring is
useful and easy for alliance members; first time neutrals frequently
end up isolated, dropped, and lost to the hobby.
I am most experienced in 2950, so I will make a stab at the nations I
would not give to first-time players for that scenario. I'm sure the
1650 vets could come up with an equivalent for 1650.
Frustrating/difficult positions for new players:
Northern Gondor, Sinda, Northmen, Dragon Lord, Rhun.
All of the first four can face sustained frontal assaults in the first
few turns that can cripple them. Poor play by Northern Gondor and the
Dragon Lord also badly hurt their respective teams. The Rhun are here
because they frequently face join-or-die threats that make for a poor
introduction to the hobby.
The Witch-King and Woodmen can also be in for an early hurting, but in
my experience of a dozen games they are rarely on the ropes in the
first five turns. 2305 is hard to reach and the Woodmen have lots of
neighbors who can help them.
Key team positions:
Noldo, Cloud Lord, Dark Lts.
All three of these nations have special importance for their teams.
The Noldo and Dark Lts. have powerful artifacts and access to crucial
lore spells for the artifact chase; they also have very strong and
expensive characters. The dark side relys on the Cloud Lord agents
and the economic muscle that comes from not needing armies.
Southern Gondor is very important for the free military effort and
when properly played it is an economic powerhouse; the Dog Lord is
also very important for the dark military effort. Either or both of
these positions might also qualify.
It is perfectly fine to have a learning experience for the first game,
but it should not come at the expense of 24 other players. I have
seen lots of aborted games that can be directly traced to drops and
inexperience in the nations above.
Well, thats my two cents for now. Fire at will 
cheers,
Marc Pinsonneault