[MaHuJa]

Currents, at least, have a tendency to behave weirdly, regarding things like cavitation speeds and the like. I never investigated if it made sense or not, but few missions use currents in the first place.

In a few missions, waveriding may cause a bigger problem, since a sub may pitch too much and hit the bottom if surfaced over a shallow area, e.g. the start of sicilian wedding.

With most missions, that have more than a couple units, all but the most powerful computers will have trouble at the max of 16x, so I don't see the need to increase it further.

SC used a stepping 1-2-4-6-8, DW does the "binary series" 1-2-4-8-16.

The interfaces for the subs are mostly identical, and the improvements are rather subtle. For example, the esm station now also shows the emitter you are detecting. Or the enhanced acoustics model, which can only be seen in the behaviour of the sonar, not in the sonar screen layouts.

One last thing about waypoints - you can doubleclick on a waypoint to set a new speed, depth, etc, but so far I do not think it works...