I too would very much like to keep the TH&B station on Hunter St as Hamilton's intercity rail station, mostly because its right downtown. But we have to face a very expensive reality.
If the TH&B station is to handle GO, VIA, and maybe even a
Hamilton centred commuter network, then we need to connect the station with the CN main line that runs along the lakeshore in both directions.
To the west of Hunter St station this connection has been partially made. I say partially because there is a 700m long single track tunnel between the station and the CN line. The Hunter St tunnel must be double tracked in order to allow for the easy movement of passenger trains. This project will be expensive, depending on soil conditions, method of construction, location of underground utilities, and building foundations of the structures along Hunter St.
To the east of the station, things are worse. Currently, there is no direct connection to the CN main line. There is a CP spur that runs north from Kinnear yard alongside Gage, but this is a single track, low speed line with multiple grade crossings, and it does not connect with the CN line, but passes underneath it.
This spur track will have to be upgraded significantly. Because of the number of grade crossings, the line will have to be either elevated or placed in a tunnel, and in order to deal with future traffic levels, it would be best if it was double tracked now.
If we elevate the line, we're going to need a lot of land. In order to build the connection between the spur and the main line, many properties to the northwest of Barton and Ottawa will need to be leveled. Looking at Google, I would guess that Rosslyn Ave N would be cut back to Dalkeith Ave, and all of the homes on Rosslyn north of Dalkeith, and all of the homes on the west end of Dalhousie Ave would be bulldozed, either because the new rail line would be on those properties, or that the homes would be cut off from the rest of the city by the tracks (Dalhousie would end at the rail line)
Just north of Barton, there is vacant land along the west side of the spur, but not so south of Barton. Here we have a choice. Either expropriate two industrial sites on the west side of the spur, or close Belmont Ave and demolish several homes on Belmont north of Campbell. Between Campbell and Cannon there is a school on the east side of the spur, and it may be possible to expropriate a strip of land rather than the entire property.
It is between Cannon and King where the most expropriations must occur, as the spur has tightly packed houses on both sides. South of King things improve, as there is a strip of land that follows the spur for most of the remaining distance, although some properties will be needed.
If we decide to tunnel the line, then options improve. We may want to temporarily close the south end of Gage park for construction, and build a long curve under Gage park and then head northwards underneath Glendale, Belview or Belmont, and then come up to the surface north of Barton. Homes will probably be bulldozed along Dalhousie in this scenario as well.
In either case, the costs will be huge.
So it all boils down to this: Hunter St Station, which is better in terms of location but will cost huge amounts of money to get the tracks to the west and east of the station into shape, or James St North, which will cost less than 10 Million, but is far from downtown.