Hey hun,
No real experience or advice for you but I could have written your post! I'm going through the same thing myself!

With ds1, we waited until we felt ready to have another child, then we had a mc, then I had another lap, plus surgery for pancreatitis, then back to fertility treatment.... we now have a 4 1/2yr age gap between the boys. Not what I originally wanted but it's been great! ds1 is old enough to get most things himself and get ready for school etc... plus there's been no jealousy between them! This time, I think we want to try earlier (maybe in May) so the age gap would be much closer.

I would say go for it! If you know that's what you want then just go for it! There's no right or wrong age gap and you'll cope with whatever gap you have! You've been through the wringer with Isla and come out trumps so you can handle anything!