If she's lower end of normal sleep needs I wouldn't say it's too early to cap her nap. Lily is lower end of average sleep needs and needed her nap capped to an hour max from 20 months. Jack is definitely lsn and skips his nap 2 days a week at nursery. This week he's not been in and has self regulated pretty well on a 11 hr night and 35 - 50 minute nap each day.
I would try capping at 1hr 15, yes, and see where you are in a week. It may be that you need to cap more, but you should have a better idea after a week of capped naps if it's helping or not.