Here is a generic operating practice applied to your situation.Steam Situations.
For the logging and quary lines I would use small rod tank locomotives like 2-4-2Ts 2-6-2Ts and the like, or geared locomotives. The rod locomotives had small wheel bases so they could negotiat the tight curves of an industrial and or logging line. The extra weight above the driver caused by the presence of the water bunkers also helped with traction allowing them to take steeper grades. Geared locomotives, Shays, Climaxs, and Heislers, were built specificly with steep grades and tight curves in mind.
For the rest of the assignments I would use medium sized steam locomotives for the mainline runs. 2-8-0s 2-8-2s 4-6-2s and the like will fit nicely.
For the citris brach. I would use a small loco of like 4-6-0 or small 2-8-0 proportions.
Diesle Situations.
For the logging and quary lines I would use small industrial diesel locomotives. Bachmann's GE 44 ton and 70 ton locos immediatly come to mind for this work. Also second hand power like RS1s and Baldwn VO-1000s and S12s downgraded from the mainline may also be appropriate provided if your curves are not to sharp or grades to steep.
For the mainline I wold reccomend using any of the selection of fine first generation 4 axal power available from several companies. You can put ABA F units on the mainline express runs and 3 unit lashups of GP7s on the through freights that go through and set out and pick up cars from towns along the route, with a single GP unit in the locals that do the switching in the line.
On the citrus branch I would reccomend a small light weight yard or early road switcher of the SW1 SW9 GP9 RS2/3 style.
*(DISCLAIMER)* The operating pattern suggested here is only a generic pattern. It does not reflect the operating practices of any one railroad.
[This message has been edited by Challenger (edited 01-30-2003).]