I have 16months between mine, although they're now 3 and 5, and being organised helped me.
Have the pram ready with bag, coats, shoes, snacks, toys etc the night before. In the morning you can wrestle them in and literally walk out the door. I frequently used to leave the house with 2 crying children but they'd be quite happy after five minutes (food helped the toddler with that).
My youngest wouldn't entertain reins either, but if you've got a runner I think you have to stick with the pram for safety sake.
Not going out makes the problem worse though...kids are like labradors, they need to get out for a good run around twice daily!
Stick to enclosed places; soft play, play ground, library, museum etc. So what if they trot off from you? It's appropriate, they're not going to die etc.
I used to go out every morning for sanity! A couple of mornings were a group, one morning was meeting friends and the other two were errands. The days where I needed to do errands, I used to take a lunch box for the toddler. She could walk for a bit on the way (you have to do a bit of 'training' to get them to hold hands etc), and it didn't matter if it took forever. By the time we got to the supermarket or wherever, she was tired and happy to eat some snacks in the pram (and help with the shopping), and I confess I started bribery with babycinos from an early age...once the jobs were done, we could go for coffee and a 'cino which benefitted us all 😀
There are a lot of mums out there who have had small age gaps and really empathise when they see another mum struggling. I still cringe when my 2 are fighting and there's a smug mum with a sleeping baby in a car seat and an 8 year old reading quietly 😬
It gets better, honest!