Back from my trip and a bit more reflective.
I suppose the overall experience is that MEL/SYD to LHR is a lot better than LHR to MEL/SYD for a Qantas WP, travelling in Y.
But to a few of the points.
LHR check-in was supposed to open at 16:30 for QF2 (21:30 departure). Too bad if you are on QF10 (22:30 departure) with luggage, even the 1st class desk staff says "sorry, come back at 17:30". I had carry-on only so could get a BP for QF10 at 16:40 when the 1st class desk opened (about 10 mins late). I witnessed the whole process upsetting a few actual F-class passengers who were there - they called it silly, inconvenient and a step backwards (it worked better with the BA partnership, apparently). At least get the kiosks working?
The LHR T3 departures security express lane is not so well explained, if you are in Y-class. You see others scanning their BPs, but a Y-class one will be rejected. The lane staff said it was due to it being Y class. They then needed my Qantas FF card (the BP printed status seemed not enough) and even then they could not find me. So it was not really an express experience and a pretty coughpy system.
BA now only have a few European flights (with no 1st class) and one long haul (to BKK) departing T3. So I'm not sure who the BA 1st class dining room is catering to? Pretty much only the 2 x Qantas and 1 x BA flight now. And the room was 100% empty at 18:45 when I tried to get access. Apparently the main benefit of the dining room is to be able to sit at a proper table - gee, when it's 100% empty, what's the problem?
I checked-in on-line using my iPhone (via safari). You get the pdf BP, but can't do much with it. You can't even email it. A bit of an iPhone thing I suppose. But being able to print a BP again, when a printer might be available, seems sensible to me.
Re: access to LHR T3 Emirates lounge. Well, it was predicted I suppose:
Lounge Review: Emirates Lounge, London Heathrow: better than British Airways? - Airlines | flights | hotels | travel tech | style | apps - Australian Business Traveller. The CX 1st class lounge was small too, but they managed perfectly well and were warmly inviting! Something that the BA and EK lounges were not.