If you haven't tried an A350, I havent either, this might be the chance.
If SC earn is important, maybe go via JL NRT/HND, (more SC), maybe a tad more
$, ... but as you say, yours is an award redemption, so SC is not important.
Edit (ps, I do realise CI carries a QF flight number on a certain number of their flight sectors).
You might have to check and see where you will be sitting, probably no choice/limited choice.
For me, I would pay for their J to try out their contract lounge in MEL/SYD/BNE, and also in TPE coming back.
Go for it, you might not get window seats, but at the least, you have access on this possible trip into their CI J class lounge at TPE.