I think you should move. It is way better to go there as the resource nodes are far closer there than in Grassland. I even would suggest moving to the sea, near the oil but with some distances from the oil. It is easier to build without obstructions on the sea.
Plan ahead, Especially and most importantly, reserve tons of spaces on the ground floor for an eventual train station. It is important to be able to use that base in the future without rebuilding again. I then build vertically upwards.
I reserve tons of spaces on ground floor. My base has 4 tracks. Each track has 5 foundation width, 15 foundation length, and 5 steepest foundation height. It should be around 160 meters (width), 120 meters (length), 20 meters (height). It is enough space for platforms, storage containers, stairs or jump pads. It seems to be massively overbuilt but once you are in late game trying to mass produce rare stuff it saves a lot of time because you just need to belt stuff around.
I rebuilt the base in Tier 6 so I had trains already by that time. I think you should still build truck stations, lift the resources up, and then when trains come around convert it to trains one by one later. By the time I need more resources than the base can provide, I can easily move the smelting facility away and repurpose the train station to smelted materials. Very flexible.