Should I return this phone or not...honest opinions please

That's a tall order!
Like any other technology phones are a moving target - today's hot new item is tomorrow's junk. If you are caught up in having the latest and greatest good luck - it's always just around the corner.
Phones are a very personal choice - it has to fit your needs and lifestyle, normally for about two years. My suggestion to you is this - you have taken the first step and selected a phone. Read all you can about it, use it A LOT. If it doesn't work for you you have (I believe) 30 days to return it and try another, Do the same thing over again until you are comfortable and satisfied.
Also be sure to enjoy the process - its supposed to be fun!

Ditto, same reply a the two above, although think about this as well;

You did make a great choice to start with.  The Eris is a wonderful phone with its features, capabilities, options, customization, etc.  It's pretty much a computer in your pocket.
That being said, there are some shortcomings, mainly when you put the Eris up against other phones.  Comparing things will always make yours seem lesser.  As Monty says, the smart phone arena is a fast moving target.  You buy a great item today, tomorrow it pales in comparison to something else.

My suggestion:  You do have 30 days (make sure you check the date with VZW) to decide if you want to keep or change phones.
If you can spend the $$ the HTC Incredible is a big brother to the Eris.  Basically the same form factor, but with a faster processor, which allows it to react faster.  It also contains Android 2.1 as the stock OS, so you have those features as well.

If you can afford it, I'd say go for the Incredible.  If being frugal and patient is your thing, stick with your Eris, its an awesome phone, and you can tweak it to make it run right, and do things that'll overcome the issues you are having.