I am basicly a S76 driver and I always prefer controlling glideslope with cyclic. Way back in my basic IR I was thought to do it with collective, but soon found out cyclic worked better for me. And actually, when flying as an instrument instructor and see pilot hand fly an ILS with collective, they normally do a much better job when doing it again with fixed power setting. It is just one less thing to work with in IMC, and doing it in IMC is really the diffrence.
On the S76 35-40% tq for ILS is a good baseline that works for most of the time, will give 120 with gear down.
An S76 with Phase 3 is the only one I find it better to adjust glideslope with collective since it is so stable in attitude and speed.
To be honest, I do not think a 4 axis AP flies glideslope adjustments with collective, it maintains airspeed with collective (or slows it down in decel mode) and follow the glideslope with cyclic (pitch actuator). Somebody might be able to confirm/correct this.
To me it seems that most Bell pilots want to fly the glideslope with cyclic. Also for UK pilots it seems to be the prefered choice. Have no idea why in both cases.
Anyway whatever works for the individual with the least workload must be accepable
CB (hiding for flak).