Indeed - if travelling business class, will get access to lounges et al - may even be able to find decent value 1st class fares in line with what Qantas tries to get away with
1st lounges can be nicer than business lounges, but given that I would be trying to minimise time in airports and quite a few places have no 1st lounges, would not fret over lack of platinum status
If earnings on other airlines is poor , perhaps might be worth considering looking at other schemes to credit to once found the best flights