I don't do any sweeping, and not a ton of skid steer work in general, but I won't bring the loader somewhere for less than 80-90 an hour with just a bucket, add an expensive attachment and yeah, I don't think 125 is unreasonable. Obviously there's a million other factors that are relevant here., but I think 125 is a good neighborhood to be in.
Just for fun;
If I were asked to bid on a lot sweeping job.....if I figured it'd take about a day.
8 hours x 85 an hour or the loader = 680
+ 150 a day for sweeper rental
+ trucking out sand/crap
Would put me right around 1k, which is right where you are with 125 an hour
16 years experience, 10 as owner/operator.
And still not rich