Garmin needs to offer the 945 without a wrist Heart Rate monitor like the 920XT

No, thanks. No problems with HR monitor. 

Turn it off if you think the light is causing the irration.  I don't see how the slight protrusion of the sensor could cause an issue. If your wrist is clean and dry, it won't make any difference if the sensor or the back of a flat watch is making contact with your skin. 

No they don’t. Most of the problems have come down to improper care rather than any alleged allergic reaction. Once people realise they have to allow the skin under the sensor time to breath and keep the watch clean the problems go away. While there are some with a genuine allergy the removal of the whr will not make any difference to most. 

honestly, i would consider such device but due to other reasons - 1. i never used ohr, if one is a bit more serious into training, ohr simply can't beat a strap-hrm, at least not yet 2. i need to take extra care in order not to break it 3. i would gladly pay 50 usd less for the ohr-less device. but obviously a garmin ohr-less won't happen :-) 

There is no chance this will happen - but then again I suspect you would agree.

As garmin controls their own manufacturing, and the elevate sensor is their own and no longer a licensed third party device, the cost to them of integrating the oHR will be tiny. There is no way that this costs them anywhere near $50 to include, and they would sell so few without the oHR that it would likely cost them money to create the extra SKU. I suspect cost price to them is more like $5.

Maybe it would gave space for a larger battery, but as we're into the realms of 20hrs now anyway, I don't think that's a huge issue that would drive this.

With regards to the comment "if one is a bit more serious into training, ohr simply can't beat a strap-hrm," I agree to an extent, but this is only relevant for session where oHR on the wrist may struggle - for example intervals. For 80% of runs that are run easy/steady (reasonable assumption for a serious athlete who is polarising their training 'properly'), then wrist based oHR is fine and means one less device to carry/wear/configure/charge.

I would buy such a device (presumably it would be better battery wise and have a more acceptable wrist-profile - like the original Vivoactive), but agree with Gingerneil there is absolutely zero chance this will happen.