Problems with not stacking

[LDiCesare]

1) It will take to long. Right now with a few clicks I can move large numbers of units all at once and that makes playing multiplayer very easy. It seems like in the new system I will have to individually order each unit so this is going to become a nightmare for MP players.

That's possible, but number of units will be reduced. Games like Battle for Wesnoth play well and fast in MP despite being successive turns. It may indeed be a hindrance for MP, but I already think MP civ takes way too long so I can't judge. I don't mind for SP.

2) Units have also healed more quickly in cities or if they are in a stack with a unit which has the medical upgrade.

They could heal more quickly in -friendly territory, - cities, - forts, - near a unit with the medic promotion.

3) Noncombat units like Settlers and Workers will be extremely vulnerable.

No. You can stack units of different categories on top of each other.

4) You've always been able to rush building roads or what not by stacking lots of workers in a tile all doing the same job.

It was an exploit in CivI to rush build anything with a single settler and repeatedly typing 'r' for instance. Then people used several workers. Now, it's not obvious roads will be like what they were in civ 1-4, so it remains to be seen how it goes. Anyway, I don't think it's unnatural. You can only go that far by adding people to an existing project.

[Ijuin]

I'm guessing that defeated units in Civ5 will be like damaged ships in Colonization--they will retreat from the battle to the nearest friendly base (city/fortress/whatever), and be unable to fight for a set number of turns while being healed/repaired. If attacked during this healing time, then they would be destroyed if defeated.

Having the defeated units retreat thusly would mean that an attacking force could whittle down the defenders without having to annihilate them. Since the defenders would be active and ready for battle again after several turns, the attacker would have a window of opportunity to strike at cities/whatever before the defenders recover.