Welcome to CS.
Take a look here:
http://coffeesnobs.com.au/YaBB.pl?num=1340452495 especially at the second last reply which is Ben and Faiths new set up.
To put it into perspective in a minimal way, the answer to your question "...Would a machine and grinder for the sum of approx $2000 be a noticable upgrade from my current set up (experience permitting) ? Why would this be so? I need a good argument to release the necessary funds....", can be seen in Bens photos, and can also be "cupped" in your mouth when you are up and running with your new set up.*
The set up seen in Bens photos will cost you a bit more than your stated budget primarily because of the grinder, but*I have it on good authority that there are still a small number of pre end of fin year stock take sale price BFC / Diadema Junior machines left.* You can come "close enough" to your stated budget then with one of our Junior machines mated to* one of the smaller less expensive grinders (than the one shown in the photos), and it will represent unbelievably good value for money.
I believe I just ticked all your boxes :) and I hope that helps.
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