It sounds like you don't yet know what your enV2 can do. I have an LG Voyager which (I believe) has a similar calendar, alarm, contacts list, etc. These phones are not PDAs or smartphones---they are classified as "multimedia" phones.
Their calendar, alarm, and contact list can do everything that you described but they are more limited than a full PDA or smartphone.
For example, the calendar does not allow you to enter a note. All you can enter is a short title. However, you can configure recurring events and each event can have an individual ringtone. Plus, you can configure an alarm and the vibrate mode for each event. If you need multiple alarms, then you'd have to enter each one as a unique event.
The contacts list does not accept addresses or notes. But it does accept multiple phone numbers and email addresses. Plus, you can configure separate ringtones for each individual and attach a photo. Groups are limited to no more than 10 contacts because this is the limit for texting to multiple recipients.
Neither the calendar nor the contact list can be easily synced with a computer---the phones are not designed for this. You usually have to use third-party software and it will most likely be a manual system. However, Verizon has a nice contact list backup program that automatically makes a backup of your list to the My Verizon web server each evening. This service is free if you register with My Verizon (free) and have either the "Connect" or "Premium" plan (which includes unlimited data).
If you get a PDA or smartphone, you should get a full-featured calendar and contacts list that is more like Microsoft Outlook in terms of features. And they will be designed for syncing to your computer. Blackberries are famous for such systems and they are highly developed and have an excellent track record. Personally, I would be more interested in a Windows Mobile phone like the HTC Touch Pro but they are too expensive for me at this point. With a Windows phone you will have access to lots of third party software---including lots of freeware.
So the first thing for you is to learn the features of your existing phone (enV2) and decide if they are sufficient. They may very well be. If you realize that you need features that are not provided, begin to list them. After you know exactly what you want then go shopping and see what satisfies your needs.
Best regards, WiredNot