165 is not really that short, all things considered.
If you do some research you will find there is a school of thought who prefer shorter cranks or who even break with standard bike-fitting orthodoxy and claim that standard size cranks are too long. I have no opinion whether they are right or not, but just know that running short cranks is not that "crazy" of an idea.
Also apparently there is a market for abnormally short cranks for those with knee problems or limited motion, so some bike shops have made a niche service of shortening cranks.
If you want very short cranks you may consider looking into unicycle cranks. They fit normal square taper cranks but are available in extremely short lengths down to 75mm. Some adaptation would be needed.
Also, Answer makes mini BMX cranks down to abnormally short sizes for 4-6 year old BMX racers. Considering what BMX racers put them through, I would guess they are strong enough for normal use especially considering they are shorter. That's another possible source of short cranks.
I prefer slightly shorter than normal cranks (170mm despite 6'1" height) for simple reason of ground and tire clearance, and have done so forever.