If so, which fruits and other plants are you growing?
What is currently producing?
How do you manage the size of your trees?
Do you make compost, or do you only use mulch to build soil fertility?
Which climate are you in?
I’m interested to know how popular fruit forests are in this community and how others are doing it.
Yes, convert that lawn! Two plants worth considering are Prunus persica ‘Kernechter vom Vorgebirge’ and Amelanchier × lamarckii. I’ve heard great things about them, but they were growing in SW Germany, so do your own research first. What do you use for a ground cover? Clover can be a valuable ally in the fight against the grass.
I’ve heard good things about the Amelanchier × lamarckii too in context of food forests! Space is rare though so I’m not sure yet what else to get. I’m not actively converting the lawn other than not mowing it except for 1-3 times a year, it’s more that I started with the trees and am continuously expanding from there, plus some shrubs here and there and the hedge. There’s some clover already but actively converting feels like a lot of work which I’m trying to avoid.
One consideration is the seasonality of the fruits that you grow. Additional fruit-bearing plants would ideally produce during gaps between the other fruit seasons so that you have a continuous harvest for as much of the year as possible. That’s something that will be specific to your area though, so I can’t really advise.
If you toss in any native plant seeds that you can find and then don’t mow, the lawn will eventually reforest itself. (If you were in North America, I would recommend Robinia pseudoacacia.) Less work than mowing 1-3 times a year. In the beginning, pulling the grass at the edge of the clover can help a lot, and it only takes a few minutes every month or so.