You really have two concerns to be discussed ...
- engine wear
- clutch wear
ENGINE:
The extremely short OCIs are unwarranted.
Let's take the guessing out of this ... get some UOAs !!!!
Why guess when you can know?
The engine itself is very robust and does not need to be babied, as I already said. It's a very mature design and has not needed any major changes since it's introduction. The SACS (Suzuki Air Cooled System) has an oil cooler already. The SACS works just fine as long as you're progressing along at 5mph or greater as an average. I had a head-temp thermocouple on my bike and eventually I got tired of watching it, because it really revealed to me that the basic engine cooling (air fins and oil cooler) were doing their job well enough.
CLUTCH:
The clutch design is fairly decent and has no major issues, but if you're really hard on it, it's no different than any other mechanical clutch; it can only take so much heat/slipping friction before it starts to degrade. Also, if you're "slipping the clutch lots", then you're not geared down enough. Given that you describe it as mainly an off-road use bike, there's no reason you cannot drop the CS sprocket one tooth, and/or add some to the rear, for lower gearing which will reduce the necessity of slipping the clutch as often. If you've already done that, and you're still slipping the clutch very frequently, then you're going to wear down the clutches and no oil choice is going to stop the excessive wear. I don't care what you or any other bench-racing bike jockey thinks ... no known brand/grade of oil can stop excessive clutch abuse. You may end up needing to replace clutches more often than "normal". It's a dual-sport (not "duel") bike; it's not a dedicated off-road machine, and therefore the gear ratios and gear spacing are a compromise between on-road and off-road criteria. The idea to understand here is that regardless how many hours the oil has on it, if you're seriously abusing the clutch with a lot of slipping, then the clutch will develop a very fast degradation rate no matter what the oil is like ... clean, fresh oil has no ability to reduce wet-clutch wear over a lube that has 100 hours on it. The FMs and thermal transfer capacity of the lube isn't going to save your clutch, no matter how "fresh" the oil is.
Note: the UOA will tell you nothing about clutch wear, unless you've worn the material all the way down to metal-on-metal, and shame on you if it's got that far arleady.
My point is that OCI duration in regard to the engine does NOT need to be less than 2000 miles or approximately 100 hours. In regard to the clutch, the OCI won't alter the degradation rate if you're slipping the clutch often and excessively, because oil cannot stop or significantly retard clutch wear in abusive conditions.