Hello there !
Well... Yiiiiihaaaa !!!
Now i think that should really be improved a little with some nice more complete plugin.
This approach is sooo simple, congratulation. It just... works as usual.
Very few thing missing in fact, some widgets included (current issue wit a thumb, some pdf export...)
The fact that it uses the standart WP core (categories, tags, posts)AND the big one, the possibility to transforme permalink structure in order to have /issue N°X/postname/ (or whatever else after /issue/)
Some integration with Membership, of course, and, as usual, a racoon !
Once more bravo.
Dont miss this opportunity. Issue based magazine is definitly a big market. Dont miss it !