That sounds like fun, Goom, wish I could join you! To get the very best out the experience, my advice would be to use it as a numismatic education too. Namely, rather than rushing out and buying lots of coins in an excited frenzy, leaving you with a backlog of coins you can barely get a chance to catalogue properly; I'd instead pick my coin (example: say George III Halfcrown) and put the 'proper' legwork into it and learn about the mint, check out the past sales for references, see what counterfeits are around, track down some interesting articles from the BNJ, get some academic understanding about it first etc. etc. It would be so exciting to approach the whole project historically, at least that would be my approach! Denomination? I'd probably not tie myself to that but, instead, would go for what I found attractive. You can at least then navigate around some of the more popular denominations in expensive reigns! Enjoy! Lucky you!