Fagus crenata backbudding

Hey guys,
This is the third year that I have the tree, not a young one, around 35 years old ish, around 30+ cm or a foot high. The tree is getting a bit leggy and I could use some more backbudding.
The first two years were spent fixing the existing structural flaws, and moving it to a bonsai pot.
From what I read they kind of respond like pines, moving in two year cycles, current year’s care sets up next year’s growth.
This and last spring I pinched the new growth and got some backbudding on relatively new wood(maybe 4-5 year old), it’s not super strong but progress nonetheless. Once the leafs turned in fall , I defoliated and wired it out.
The small interior buds didn’t open this year along with some branches that my A** hole cat chewed the tipsoff. The buds and branchlets are still alive.
Now after leaf hardening I pruned off the shoots that I missed pinching on and got some minor push of new growth in some unopened buds.
My question is, would a partial defoliation do any good in facilitating a new push of growth?
Maybe strengthen those weak interior buds for next year.
What about timing?
I’d wait for another couple of weeks, depending on weather to defoliate, early to mid June.
Any thoughts?