For most of my Jet* flights this year, I've been able to select seats 1DEF during OLCI, except once was a bit late and ended up in 3C. I remember being annoyed with my knees hitting the seat in front of me in 3C. When I was in row 1 however, I greatly appreciated nothing touching my knees, even with the reduced foot space, I just leaned it against the divider while crossing my legs...
Of all the free seats, IMHO 1D is the best as you can still extend your leg into the aisle, while 1F has a curved wall I believe.. trying very hard to remember all that at this time, but I definitely preferred 1D of all the seats I could select during OLCI.
Oh.. all my flights were about 60-90 minutes so if you're flying from Perth.. well I have little experience with relatively longer flights =)
I agree with
BvT about overhead locker space. It can be an issue if you have a solid, barely legal

carry-on and you board mid-late. My carry-on bag is quite small (11x37x29cm) so I could fit it in most of the time, but I remember an instance where they stowed it for me in the do not stow area above row 1 and another instance where it was stowed above row 5. I had resigned myself to waiting 10 minutes when the CSM stopped pax getting off and asked one of them to get my bag

. Very kind of her as it took me 5 minutes from plane to Skybus (Melbourne) and off to the city, saving me 10 minutes
YMMV.
By the way.. FT has posts about people leaving carry-ons up front so they can just pick it up on the way out.. Does this actually happen in Australia?! I've never noticed it and I would feel so weird in case someone actually went through my stuff while I'm far off in a different row.. If it did happen here though, it'd sound like a TT or JQ thing indeed..