Thanks for explaining about the no swimming or flying units, I had no idea why you wanted to remove these.
I'm glad you are adapting the map I created, I'm not the official map crafter, it is just that nobody else seemed to want to make any
The idea for the Outcast leader or the blood train giving a different victory condition were things I was suggesting we mighty consider adding later and if needed.
I don't really code anything in WML these days (I made an era a while back but by the time I was finished the Wesnoth had moved on and the WML changed so nobody ever played it) I do not know how difficult it would be to code something which would cause the Outcast leader to choose a direction in which there were fewest enemy units.
As for the blood trail, it would lead to the Dragon's treasure or something.
However both of these (but especially the blood trail) would work best on a map with the Dragon in the centre of the map and players starting around it. Since we are not using this they would not work in the forms I suggested - the Outcast leader could work if it were adapted, the blood trail I think we can agree won't work at all.
Also, re the no flying or swimming units: Wesnoth teams are balanced as they are - as you can see, I'm all for innovation or adaptation, but creating new factions or removing units from existing ones would mean that you need to re-balance the sides.
I don't understand the part about using chasm and deep water as the obstacles (only obstacles?) but I think that for now it would work best if we make one major change at a time perhaps