Thanks for the note here, mykkal. We appreciate your feedback on this and you taking the time to give us an overview of your thoughts on this.
I do want to clear up a couple misconceptions here, though...mainly your claim that this plugin needs to be PCI compliant per federal law. If you check out this PCI Compliance Guide (http://www.pcicomplianceguide.org/) it specifies that:
PCI applies to ALL organizations or merchants, regardless of size or number of transactions, that accepts, transmits or stores any cardholder data. Said another way, if any customer of that organization ever pays the merchant directly using a credit card or debit card, then the PCI DSS requirements apply.
However, since The Events Calendar doesn't involve financial transactions of any kind, it does not fall into that category.
You do make an excellent point about 301 redirects, though. While we didn't have these in place for sites jumping from 1.x -> 2.0 (which was more than a year ago at this point), we are incorporating them for the impending 3.0 release.
Regarding your broader point about the switch from events as posts to a custom post type: this was a conscious decision we made based on feedback from the community and trends we saw regarding where the industry was going. Custom post types were increasingly the norm at the time we made this switch and we found users would by and large prefer to treat their events as a separate, custom post type loop that they could then integrate back into the main loop as they wanted to. The current releases offer a tutorial for how to do this; once 3.0 releases, there will be a setting that allows you to have your events appear in the main blog loop as well, to help users in your position recreate that original behavior as they see fit.
Hope this helps, and sheds some light on the process. I apologize on behalf of the whole team that the plugin in its current form wont meet your needs. Hopefully once 3.0 has launched, you'll be interested in giving things another shot. Best of luck finding a calendar solution in the interim and please let me know if you have any other questions, thoughts or concerns.