My older daughter ( who is now 5) didn't nap well at daycare until about 2yrs old. She would maybe take a 20 or 30 minute nap, so what my pediatrician said at the time was to make sure she got at least 12 hours of sleep at night, if I could more, but with a work schedule and commute time it was hard to get her ready for bed earlier than 7 and up at 7am. So that is what she did. She was similar to your son, very easy going child and really didn't see a change in attitude or behavior when she didn't nap well.
She moved into a toddler room (around 16 months old) where everyone was put to nap everyday at 12pm, with lights lowered and classical music on...that was the first time that she finally got into a groove of napping. It increased to about 45 minutes of sleep at first, after about 6 months she would take an hour and a half.
On the weekend I kept the routine the same, she was put down for her nap at 12 with classical music, read the same story to her everyday for nap and bedtime, told her we were going to read a book, not going to bed, because she would would resist otherwise. When she was around 2 or 2 1/2 she started to "catch up" on her sleep on the weekends and would take a several hour nap. That was what we did and as her naps increased at school, which was over the next 2 years, her naps on the weekend evened out with during the week. Her nighttime sleep stayed the same during all of this.
So for us the consistency and the "peer pressure" of everyone sleeping was what got her to nap, but before that just making sure the nighttime covered the need was what worked for us.
Good luck.
E.