It's been a while since I made a list comparing CoW1.0 with CoW1.5. Not everything from my list after CoW1.5.2 still is relevant - time for an update:
Positive (sorted from really great to rather small details
* Units not upgrading automatically: Absolutely vital breakthrough. That's the best improvement CoW has ever seen. Now every research decision is interesting and researching & producing a broad variety of units is a good option.
* The new production buildings - players now have to invest into having sufficient production capacities and destroying/conquering them is nice as a new strategic goal.
* Number of production orders a player can and should give in CoW1.5 increases only slightly from early to late game, which is much better than the slow start in CoW1.0 and the production orders click orgy in CoW1.0 late game.
* Doctrines added. Almost perfect at first shot. Good work, Bytro team.
* Fighters and rocket fighters offensive focus. In theory a very good thought. Only in my experience doesn't really work, because the bug that planes performing a direct attack on a patrolling or travelling (maybe also landed) air stack suffer more damage than you should expect from defender's stats still seems to be there. Had about 10 such battle results in CoW1.5 and every time the attacking stack suffered about twice the damage that it should get according to stats of the attacked air stack (and no, there were no other stacks patrolling the area). So if 1 fighter attacks an equal fighter with direct attack command, both suffer same damage - although attacker should get only half the damage. Does somebody else have more experience with this than 10 battles and can verify or falsify this observation?
* Commandos having stealth and ignoring fortresses instead of superior front-line power.
* Rocket artillery and attack bombers added.
* LT and MT having offensive focus. Is acceptable from realism perspective and improves the game tactically.
* Range of capital influence on morale depending on map size: A really very good change.
* Morale bonus of fortifications has been removed.
* Researching transport ships now makes sense on the world map. Well... at least sometimes.
* Rocket fighters now having a second research level.
Negative (sorted from really terrible to small details
* Same HP progression for all units.
* Manpower as available workforce instead of manpower as recruitable soldiers & all units same same. If each unit branch had it's own powers (infantry cheap upgrades because upgrades should have 0 manpower and food costs; ordnance low research costs; armour high speed and HP progression; planes high speed and range progression), that would be much more realistic and interesting. Already outlined recently in --> this post <--.
* High unit power progression and doctrines blur significance of K/D very much. It's good you made a first step by giving higher level units more military ranking points than low level units. Now all that still needs to be done to fix K/D is (fingers crossed you get that done
- Displaying military ranking points in the unit detail view.
- Adding a counter in DB for ranking points scored from kills against human players. Initialize it with units killed so far * ranking points units of that type gave so far (in CoW1.0).
- Analogically a counter in DB for ranking points other human players gained from killing your units.
- Displaying the quotient of these two new counters in the player profile either instead of the current K/D or next to it.
- Ideally reducing ranking points of Comintern units by -5%; increasing ranking points of Pan-Asian units by +5%; increasing ranking points of Axis units by +15%.
* Centralization of resource production to cities. Very unrealistic. Cities as main source of money, goods and manpower OK. For food, oil and rares totally NOK.
* Almost all AI countries giving same number of victory points and almost all AI countries having similar power. Now Luxembourg is almost as important as Austria or Bulgaria, Iceland as great as Portugal, Villa Cisneros as important as New York and so on. That's trash. Why have the maps been designed like that?
Oh, you don't know where Villa Cisneros is? I hadn't known either, before start of CoW1.5. Proves my point.
* Centralization of victory points to cities. Really ugly.
* Infantry cannot be recruited outside cities. At least militia should be recruitable also in rural provinces.
* Attack timer reduced to 30 minutes. Makes you have to come online even more often. In other words makes it harder to have a healthy real life while a game is ongoing.
* AI seldomly researches and builds higher level units; also in some cases hardly builds units at all. Defeating AI in mid and late game is too easy. But I bet you know that (-; ... probably isn't easy to solve.
* Strats offensive focus against planes. Of course I remember you can't change that easily without giving them defensive focus against ground as well. But added it to the list nevertheless, so you don't forget that's still a task.
* As some others already wrote, railway guns are OP. They should make sense in a few situations - mainly if defending or attacking a fortified position. But in open field battle, RR guns should be clearly inferior towards regular artillery. I would reduce HP of RR guns, because in reality they were not that difficult to destroy.
* Huge 2D flags instead of the nice, unobtrusive flag pins to mark the capital.
* The damage output that plane transports have should be displayed in their unit detail view.
* Too tall city names on the map. Is ugly.