Limit of 4 sea spaces was an optional rule (sea movement was reduced by one hex to a minimum of four per corp carried over X, I forget the particulars. We used it once then dropped it).
In the board game, you cannot ally with a nation for one year after the end of a war or the breaking of a treaty. Thus Fr would not be able to support a nation it just defeated if GB wants to then attack it. By the rules, access can only be granted to an ally, though I have played with some who house ruled that to access can be granted to anyone with permission. This rule prevents such abuse as GB sailing its army in a port, be it major or minor, without permission, so it will not lose the army by failing to disembark, but GB wants to be able to set sail and continue with the army, which requires a port. Likewise, major powers cannot just take a shortcut through another nations territory, or try to hide in superior defensive terreign in a minors territory.
The French are not all powerful. Considering the average 10vp an eco phase needed to win, I am not surprised that I have only seen france win in the hands of our best players, while even our average players could win with russia and GB. France has to be a masterful player to avoid the often inevitable coalition against it AND to stagger wars out to stay on the high end of the political status sheet.
If this game is half the board game, it will still be exceptional. I have seen some wild stuff happen, all of it fun, from the fight the brits couldnt lose but managed to throw three ones against three sixes by the turk, to 50 spanish factors obliterating 20 french factors under Davout and Davout being captured, to the might Au gaining control of Sweden and a few game years later pronging the poor russian from north and south, with his might navy of 21 ships and an inherient -1 mod to its die rolls beating back the full russian navy, blockading the port, then the swedes taking the city and causing the scuttling of the russian navies, the death of Napolean and Wellington in the same battle and the use of those three six sided dice for target practice the same day...this is a great game.
However, I do agree Fr and GB should start at war and only be able to surrender via unconditional, with or with out the mandatory picks required in the table top version (unconditional access and remove two fleets are what the french demand, with one option left for them to choose, while the brits demand the removal of Napolean...one neat rule from the table top game, to remove a leader, all nations involved in the peace had to pick that option, and I have seen GB left hanging when his allies balk and want other conditions...unless GB payed them).
Now, it has been many years since I played EiA, so if I miscall any of the old rules, please forgive me.
...nothing is more chaotic than a battle won...