3 years and 1 month betwee our two.
The good-
DD1 is very independant and can do lots and lots of things on her own, not always needing my assistance.
DD1 understood what was happening right through my pregnancy and bring DD2 home.

The bad-
She still demands alot of attention
It's harder to have play time with her(would happen with any age though)

I like our age gap, close enough without being too close IYKWIM? we're thinking about trying for number 3 when DD2 is 12 months old.

I really dont think theres a better age gap to have another child, it all depends on what u can cope with i didnt think id cope with a dependant toddler and a newborn thats why we waited as long as we did, but now i think i'll be fine with it.
Good luck making a decision