Okay, you were actually there I was not, and yes pics can be deceptive with angles etc... Lot of live looking foliage on the ground though
I take on board what you originally wrote about the concern that your client had about a previous failure, and you not wanting them to top this tree.
My 2cents........you're on a hiding to nothing with the existing multi-stemmed strucutre of the tree that almost braided effect those codominants have created and the continual competition for light and apical dominance makes it a complicated example. (It looks like regrowth to me from a stump that is buried in that raised bed) Removing crossing and rubbing branches (where they have been significantly compromised) would certainly have taken a fair chunk out of the tree's live canopy.
Just as with any pruning that envolves codominance if you can, reduce rather than remove.
When it comes to reducing the sail or wind loading effect on the canopy it pays to recognise that very small reductions in height make a big deal of difference in loading.
Eucs all most all have a growth pattern in their foliage that is very end heavy, even trees that have not been pruned ever can and do look lions tailed...it makes any kind of pruning of trees older than juvenile age class something of a headache!
Personally I'm not convinced that opening the internal canopy results in better resiliance to storm events, what I personally believe is that you can expose limbs and branches to angles of wind loading they have never been accustomed to and that can lead to failures in itself....rather like edge exposure in forest stands after clear felling.
If there are concerns by clients about limb and branch failures, yet there are no visual indicators then I would be trying to argue for improvement of the health and vigour of the tree...look to the soil and roots...in the case of your pic there are some problems there that I think you are well aware of.
With pruning I feel its nearly always about dose, and this is intimately linked to the species/age/health/vigour/environment/target so on....
For me Danny you took too much off, but outside of the deadwood and weakened crossing branches the real problems for this tree are in the ground.