Hello and welcome to BW forums
Although the first A time is a bit longer than the guidance for his age it looks like it is resulting in a good nap. I wonder if really the next A time needs to be a bit longer too so that he can get another good nap rather than just 1hr? What do you think?
With the sleep training. I totally understand having LO sleep in the stroller, in fact mine refused to sleep in the stroller which caused me lots of difficulty so I ended up feeling I should have used it more so we could get out more rather than chained to the cot!
Are you using the stroller for all day and night sleep? I see that with shush/pat you are putting down in the stroller so perhaps you are using it for all sleep just now like a crib? To be honest, based on my own experience I think I'd continue to let him nap in the stroller as you have been and just rock it a little. Rather than changing the way he falls to sleep by trying to shush/pat in arms you could instead reduce the movement of the stroller gradually over time so that if he is starting from a point of needing lots of movement you eventually end up with little or no movement needed and the ability for him to stay asleep through the transition from one sleep cycle to the next without necessarily having to rock or walk the stroller at the transition time.
The benefit of him having learned to sleep in the stroller (apart from giving you some freedom to get out) is that he has already learned to fall to sleep with his weight on a flat/mattress surface rather than in arms. it seems counter productive at this point to now be teaching him to fall to sleep or become drowsy in arms before putting him down. I think instead I would do the wind down the way you used to, a cuddle or song etc in arms, then into the stroller and move him in the there, but reduce the movement the way we would usually reduce shush/pat so that gradually he learns to sleep without it.
An additional 15 mins on his second A time increasing from 2hr 30 to 2hr 45 might help in extending the nap length and also in how much rocking/moving the stroller is needed. Initially begin with lots of help, then gradually reduce.
If/when you want to transition to a cot or bed for naps and night sleep you can tackle that at the time. Transitions from one sleep place to another can be difficult even with independent sleepers and you are not necessarily going to avoid that difficulty. Having him trust in you and you being able to sooth him and support him will be the most helpful aspect of getting through changes will be the best start to any changes which might happen in the future.