What spindle are You using now ?

You mention "productivity" so it hints at a business.

If it is a business and productivity counts as in making more per day, You would maybe / possibly be better off with a Nakanishi or NSK spindle.

They are *insanely* good and near silent at 30-50-60.000 rpm.
1 micron runout guaranteed.

Last near forever (internal air cooling with the internal included silent micro air compressor).

An NSK spindle would probably double your productivity, or more.
Lower runout makes bits last 2-5x longer, mostly, in steels.

Likewise, industrial tooling has bits that are very short, and with thicker shanks.
If you could shorten your free length just a bit, a huge increase in rigidity => longevity results.

I might be, perhaps, be able to get a discount from your local NSK rep.