If you are referring to the 50% requirement on a VA "marketed" flight, it is relatively easy to get flights with VA flight numbers. You can book with any of their partners on the partner's website (or VA website), generally speaking (some caveats), as long as it's a flight also sold on the VA website, and you enter your Velocity number, most of the time you'll be fine. In other words, a flight sold as a cash fare on the VA site usually also has a VA flight number; it doesn't need to be VA metal (that's mostly irrelevant). E.g., I booked Air Canada, Sydney to Vancouver return on the Air Canada website in Economy, entered my Velocity number, and this counts as a VA marketed flight (as long as it's a fare class VA sells - e.g., don't book a cash premium economy fare - needs to be economy or business).
Note, if booking with Air New Zealand, make sure you book via the VA website only (slightly different arrangement), and it's not on a competing route with VA (Queenstown - ACCC requirement), and departing and returning to Australia flights only.
If you booked on the Qatar website to say London, all flights Australia - DOH have a VA flight number (not just wet-leased), then the second leg would still earn status but count towards the other 50%, which is still important. Not sure about others, but the 50% marketed flights requirement hasn't impacted me at all. What have others found? Genuinely interested.