The P42 has been a major suggestion ever since the release of the first game, and I could see it as an addon for the Oakville Sub. Via rail operates P42DC's, so it would be perfect to make a loco add-on for the Oakville Sub with a via rail p42. The SD70M or SD70MAC are also popular mainline locomotives that have been missing from the game, and it adds more variety to American freight routes. I think that a UP SD70M add-on could work with Sherman Hill or Cane Creek. As Union Pacific are major operators of these locomotives Again, it's only a suggestion
The UP SD70M is needed. I really want all variations of the radiators and cabs. We should also get the newly repainted Abraham Lincoln #1616 SD70M. We should get the ATSF and/or BNSF SD75M/SD75I variants too, along with NS SD70Ms and SD75s (ex-ATSF/BNSF) and CN SD75Is/SD75IACCs. The P42 in VIA and Amtrak liveries is a needed locomotive in game too.