It is possible to build rail depots on tracks which are owned by the public player, but it is not permitted to build rail depots on tracks whose electrification belongs to the public player. This seems like an odd discrepancy -- surely it should either be permitted in both cases or prohibited in both cases?
Maybe rather prohibited in both cases.
There is something similar with removing ways: public player's ways can be removed, but not ways with electrification built by public player (this holds also if the way belongs to the player).
Imo, removing public electrification should be allowed.
If I own a way which is later electrified by the public player, it's not clear why I shouldn't later be allowed to build a depot on that way. Yet under the current behaviour, such a depot would be prohibited.
Public player way should also not be removable. (PUblic player: Grey color, not to be confused by unowned: orange)
The depot should be allowed on unwoned (getting owned) and only look at the way ownership.
Players should be able to remove intercity roads (which are owned by public player), though.
Why? Especially in multiplayer games the should explicitely not allowed to do this. Otherwise you can easily kill a company overnight.
Allowing diagonal level crossings (rail over a diagonal road) would go a long way to alleviate the need to remove public roads. Otherwise a diagonal intercity road is quite the barrier to building a rail network. IRL, if grade seperation is desiered, the road usually gets the bridge and not the rail.
In real life, such a project would involve cooperation between railway company and the road owner. It will be the same in Simutrans. Though Simutrans also has the orange roads, that are open for everyone to demolish. I don't think such road exist in the real world, except maybe some poor states with no control.
You can do a diagonal crossing with tram tracks. Or build a bridge, which is quite often also required in reality.