Small wins indeed.
If DS is usually extending his naps and they are lasting for 1.5h+ without waking, then I would move naps into the big cot upstairs. However the process of resettling is more difficult in the cot (I find) so if any re-settling is still needed then I would keep in the pram.
I used a bouncy chair, but same premise with a pram. Keep in mind the long-term view of weaning off movement. While you might need to rock the pram to get him to sleep and to resettle if waking up too soon, be mindful of doing it less. Be slightly less vigorous. Rock for less time, rock slower. Its a gradual process of lessening the dependency on the pram moving.
Once baby is sleeping for longer naps without needing a re-settle, I would take that as the time to focus on cot sleeping for all sleeps. Others move to cot sleeping sooner, like now for you, and develop resettling methods if baby wakes early.
Also, feed to sleep or not?
Feeding to sleep isn't ideal. If you have other means of settling (pram rocking, dummy, co-sleeper cuddling) then you shouldn't need to. I used the EASY structure as a means to both separate feeding and sleeping (baby is fed upon waking, not upon going to sleep) and give structure to sleeps and feeds.
EASY is a repeated cycle of things that you do in a certain order. If you pay attention for a while, you start to notice routines that develop. Coming from your baby, not you.
E - Eat - Full feed upon first waking up (notice the time)
A - Activity - This is happy/awake time. Because baby is fully fed you can be sure that the very first sign of a grumble or not being happily awake, then it means baby is tired. No confusion as to why baby is upset
S - Sleep - Notice the time from waking to going to sleep and also how long the sleep is. You can start noticing baby-led patterns and so anticipate awake time and asleep times.
Y - You time while baby sleeps.
When baby wakes up, start again with E-Eat and repeat the whole cycle over and over again all through the day.