On a finished lawn, you will want the lightest compact or sub-compact tractor you can find that will get the job done in a reasonable amount of time while not producing damage which will take time to repair.
On raw dirt, a higher-powered, heavier machine will be more productive in dirt or material moving. Most tracked ss's are heavier and higher powered than the typical small CUT or sub-CUT.
For mowing, both are out-performed by a dedicated zero-turn or front-mount mowing machine. The tractor with a mid-mower will get the job done, but will be slower. A brush mower on a skid-steer can be productive.
For plowing snow, I would rate the tractor and skid steer about the same (for similar HP / weight machines). A skid steer with tires may be easy becasue the tires will always be worn down and its low ground clearance. Both are out-performed for residential driveways by a 3/4 ton plow truck simply because it can drive to the next house a lot quicker.
The other poster is correct that a lot of land-scaping involves drainage work which means a trencher or back-hoe. Both the tractor and skid-steer are going to be about the same for this. The back-hoe is expensive on either, and so is a trencher attachment.
Irrigation install typically uses a small trencher and/or vibratory plow. Probably a toss-up on this, but a dedicated machine or maybe a walk-behind mini-loader with these attachments might be a better choice for smaller areas.
Small tree planting goes quick with a 30" tree auger - the skid steer will have more hydraulic capacity to run this, but can they can also be fitted to a CUT or a mini-loader.
For sod install prep, a skid steer with a grading bar does a good job, but so does a CUT with the right box blade or the CUT can also use a grading bar, but not as efficiently.
Initial cost is related to profits as well. A lower cost machine that can do a bunch of jobs so-so may be a better investment for a small business when first starting out. As the business grows, specialized machines for each task will be more competitive.
- Rick