I'm quite sure, as happened many with other locomotives (differently of Dash 9), that new ES44 will be an independent locomotive as part of SH pack (product/folder).
Good improvement in the UK routes with more TS2012 vegetation (hopefully the same on SH), enhancing the eyes-candy.
Nice new and smaller F4 HUD (can be modded/reduced even more), but unfortunatelly it seems they didn't touched the instruction's screen (popping up in front and in the middle of screen), once Quick Drive (a welcome sort of freeroam), doesn't use it. Don't expect QD working in single lines long sections, UK routes have usually multiple tracks, and RSC is a British company.
The Relay Play must be the (a sort of) multiplayer version (maybe only relaying essential data when really needed, ie close to the meetings' time).
I can see further problems with standart scenarios and local/regional versions of game, but with the new Quick Drive feature it seems they are no long worried with "standart" scenarios. The same that happened with when was created F4 to be used in the place of RailDriver console.
Excelent and amazing eyes-candy game for gamers, no doubt. For sure I'll be on board, and happier
Hard core users' life moves onwards... as is, no problem at all.

We survived so far... and still will, for a long long time.

Who doesn't have dog, hunts with cat.