I'm similar. I play with 10% survey speed.
To maximize deployment time per long-term MSP cost, I build fighter-sized surveyors with no engines, 1x survey sensor, 1x bridge, 1x engineering spaces, and 2.5t of maintenance storage.
With duranium armor, I can get 48 months of deployment time on these, and it is pretty rare to suffer a maintenance failure between overhauls.
As armor tech research reduces the weight of armor, I add deployment time to subsequent design iterations.
The bridge is optional.
Without it, you don't get the Survey bonus from the ship's commander, but you can use that 50t for a much higher deployment time.
For example, you can have 170 months and also add 1x Engineer Spaces - Small, while staying under 500t.
I use tugs to move the surveyors around.
The tugs are my standard small tug design that I'm going to be making a lot of anyway.
They have a single 2kt@40% commercial engine and an unladen range of ~60Bkm with typical starting tech (Nuclear Radioisotope with no Fuel Consumption reduction).
Range with the surveyor in tow is ~51.5bkm, and this is almost always plenty for an entire deployment.
I build commercial jump tender stations and deploy one at every new jump point.
The surveyors almost never have to wait for a tender. (Only in those rare cases where the very last survey location finds a jp, and the surveyor is closer than the waiting tender-mover.)
The tender stations are also tankers; surveyors that do run low on fuel can top up at their next transit.
I also establish a small colony in every system as I explore (assuming some reasonably habitable body), complete with a couple maintenance facilities.
When surveyors are due for overhaul, they don't have far to travel--and since only the surveyor is military, two maintenance facilities can handle four concurrent overhauls with starting tech.
Anyhow, long story short, this approach has greatly reduced the amount of time I spend on surveyor micromanagement.
Ship exceeds maximum deployment? Send to overhaul (after finishing current order).
Event says system survey is done? Move surveyors to next system.
Found new jp? Send tender mover and colony establishment fleet from staging point (previous jp), and create and send new tender mover and colony establishment fleet from home to staging point.
I have done similar setup in my games as well, although when I play campaigns where I have four, five or more human run empires I really need to cut down micro and mouse clicks to a bare minimum while still being reasonable efficient. But I have had similar approach as you do, using tugs especially. But eventually I quit using tugs and tractor beams other than to tractor proper stations around, the tractor beam can be sort of abused a bit much. Like avoiding the military maintenance cost for your explorer fleet for example, or dragging around sensor pods, magazines or other parts with regular ships. At one time my "ships" were mostly huge military hangars that I dragged around with tugs and mini tugs that dragged sensor pods around. Ships were not really ships but a series of modules attached to engines or a core ship part.
When you use tractor beams on ships they also become much smaller and harder to detect, especially with cloaking tech as half the ship is attached through the tractor beam.
At the end it just became a bit weird and I decided to stop using tugs like this. I sometimes wished that if something is tractored it should become completely inert and can't be used until you release it, but in general it does not matter as other probably enjoy it as it is and I can just put the limit on myself anyway so no big deal.