I found the tutorial annoyingly difficult despite (or perhaps because) of having been playing CiM1 a while: I know it's difficult to get this right especially with complex strategy games, everyone's focused on getting the game right for release etc, but if it ain't done well people will say "Hell, I can't make head or tail of this" and tell all their friends that. Paradox titles like EU and HoI also have this problem with in-game tutorials but they do make sure they have comprehensive manuals and sometimes even more comprehensive strategy guides available from the get go.
The second problem new players are going to face is the huge first map in the campaign - it's basically like falling off a cliff after the limited tutorial - "Where do I start?". It would have been better IMO to have a more detailed mini-scenario to work through first with some specific suggestions as to routes etc via the mission system. Also, IMO, specific details about game mechanics such as how to create a route, how to lay track etc are better dealt with as a series of short videos accessible from the main menu so you can first watch and then do, then watch again if you forget. Galactic Civilizations 2 had this and it worked really well.
Anyway, specifics on what I found annoying and difficult in the tutorial as is:
1. By the time you get to laying tram and metro tracks it's night time which makes it extra difficult to get the fiddly bits right (even if you noticed the option to brighten night time).
2. The ability to bulldoze errors on your first tram track appears to be switched off (although restored for the metro line)
3. It is almost impossible to see where you have and have not successfully laid tram tracks when you are zoomed out, leading to an almost inevitable unholy mess and total confusion.
4. There seem to be some finicky rules about connecting sections of tram track and these are not explained at all. When you select a section of double track only one side is highlighted. Most often when I tried to get the track to go round a corner I managed to connect the right track to the left which scuppered the attempt and meant I had to restart the tutorial (no save). The tutorial should explain why it works this way, what you must do to get a regular double track to turn a corner, and how you select individual sides for special purposes, a loop for example. It's too easy to get completely wrong.
5. I wasted a lot of time attempting to place a metro depot underground. The tutorial should explain you can't do this and suggest you put it on the edge of the city.
6. There is no mention at all in the tutorial about the page-up/page-down level control which is necessary to know to build a metro in the tutorial. I found it eventually in the manual after much confusion and another restart (Grrrr).
7. The one-click propose extend line, another click propose extend it further, double-click actually build it (and pay the money) mechanism is not obvious and should be explained.
8. It is not explained that you have to have either a loop or a second depot to turn metro trains around. This is totally counter-intuitive as IRL all metro trains AFAIK can be driven from both ends. That's what happens on the London Underground anyway. More frustration and another restart (double Grrrr)
9. The final frustration, having established you had to make a loop to get your metro train to return to base and therefore establish a line, was getting the track to loop round and merge with itself. I tried this for ages trying to figure out why it wouldn't do it. I burned 200m in loans trashing the track and rebuilding it in various ways to no effect. I got really, really fed up with that red line that told me "Sorry, mate, no can do(ha ha ha)". Eventually I hit on the idea of trying to make a small spar off the target for the merge which to my amazement it let me do, and then to my relief it let me join loop end onto that. If this is some sort of bug IMO it needs fixing licketyspit, or if not the exact instructions for doing this need to spelled out in the tutorial in terms that idiots like me can understand.
