I do not believe that Mr. Ross had any templates.
My count puts the number of Ross courses at 420 (designs). That is 7,560 holes. I believe that the patterns emerged as he designer more and more. The work of his major Associates (Hatch, McGovern, Aeneus Ross and later Maples) is very much like his own. He saw a great number of his courses in one form or another.
Do some of his ho;es repeat?
Sure, there is an uphill short par four on many of his courses, often near the end of the round where he would rise toward the high elevation for the finishing hole tee. He built many end of the earth short fours, uphill and blind with a nasty green. His par threes range from 87 yards to 246 yards. Many of his courses had two short, one medium and one long. His long par threes are rather distinctive and easily stand up to whatever is being built today.
Ross just plain used the earth to create the golf course. If something was in his way and he could move it, he did if he needed to. Most of the time he just employed whatever natural features he could find.
One little nine hole Ross course, Petersham CC, has one feature on the property a hill of some 40 feet in elevation change. Ross used the hill on six of the nine holes on the course creating a challenging routing from little whole cloth. Two of the holes not involved with the hill take the player out to and back from the hill.
His par 5's ranged from 450 yards to over 670 yards (CC of Asheville). As Brad Klein mentioned he did design many 485 yard par 5's. I believe he had an element of risk reward in most if not all of them. They make exceptional long par fours today.
Ross probably built some 415 golf courses in his career from 1901 to 1948, three hundred and seventy seven of those courses are in play today the vast majority with their original routing. I've played 247 of his designs and can honestly say I have never seen two holes that were identical. That tells me that if he was working from templates, he hid it pretty well.