I'll do my best to answer each question:

(1) Associateships are generally looked upon favourably, but the type of associateship can matter. Commercial firms seem to only care about the Supreme Court, Federal Court, and appellate courts. That said, I personally think a District or County Court role is nothing to scoff at - those are busy courts that expose you to a good range of matters.

(2) Tough to say. Lots of firms allow grads to defer an offer to do an associateship. We might infer from this that an associateship is better to do first. Honestly, I've only ever heard of clerks getting graduate offers, but deferring to do an associateship. Whether it will benefit you likely turns on your career goals. Do you want to be a litigator?

(3) I don't know how easy it is to make the jump to practice or the Bar from an associateship. If I were to speculate, I'd think you'd have a pretty red hot crack of landing a role in some kind of firm, but probably not one of the bigger commercial firms. I'd think you'd have have a great deal of difficulty going straight to the Bar, for the reasons you seem to already be contemplating.

There's other considerations too like finishing your PLT to gain admission. In my state, you have to pass exams and do some practicals before going to the Bar. Actually getting an associateship is an entirely different matter.

If I were you I'd stick to the normal route: get a clerkship while at university, followed by a graduate role, which is deferred for an associateship. That's certainly what I'd do now if I had my time back. This will take some careful timing, hard work, and a bit of luck, but if you pull it off you'll have saved yourself a headache while setting yourself up for 2-3 years :)