The 7250 is very user friendly, it is very easy to install Verichat on a Verizon 7250 just simply by typing: http://www.verichat.com/ota/VeriChat.jad
Into the BlackBerry Internet Browser.
The download just takes 2 minutes on the Verizon. No hassles, presto, and it works right away! This actually works on an out-of-the-box Verizon, no configuration needed. You don't even need to enter any APN information.
Also, don't get a Sidekick before you read this thread: "Push" available with non-Blackberry devices?
Verizon lets you upgrade phones before your contract is finished - why not go for it? The 7250 is so vastly better than the 6750 in so many ways, much faster performing, has TCP/IP stack, etc.
You can also be set up on BES, and avoid using BES email. Just keep doing all your email through the BWC and ignore your BES. You can use BES only for MDS - for the use of TCP/IP internet access. You can change the "Using:" to "Web Client" instead of "Desktop", and you can make that your default, I believe. Just make sure others don't send any email to the email address you set up on your BES. (You could ask your administrator to set up a dummy email address on your BES, one that nobody else uses ... and keep using your existing corporate email address on your BWC, if you hate BES that much .... but I don't know why you would want to do that. The point is that you don't need to use email by BES)