I may be wrong but you seem to be grouping all 4 of "this year's crop" as managers who have bought there way to the ABBL. I'm not going to argue on behlaf of the others, but personally I've never bought a player to get me where I am now, granted I was lucky to get Bogan which is probably why I am here. But I haven't and won't ever buy a player to get me or keep me in the ABBL.
My plan is to "yo yo" between the leagues and looking at my economy page atm I'd say it's reasonably effective to this stage.
I have a training plan and have stuck to it, which has yielded me a couple of young stars which I hope to continue to train in the next few seasons.
Effectively I probably accidently got to the ABBL, but that didn't hinder my plan at all, it helped if anything to gain more $$. I will get to and stay in the ABBL when I feel my team that I have built not bought is ready and that's my plan and has been for a while, so don't say I don't and haven't planned.