The Texas answer. Some folks in Houston have 4WD Ram 2500s to drive to Starbucks and back. Some have a Prius and borrow their mother-in-law's Ram when they need it. Same way with the cart. You have to decide what bells and whistles you need and your like-to-haves.
We turn on the Display Logs first (in the Modules >> Plugin Manager), add Mod List, and Clone a Template as a basic operational setup. We clone the responsive_classic into something named more to our liking and have the original as a fall-back when testing.
Next either PayPal or Square for taking money. We add One Page Checkout for the customer's convenience.
From here, you can add products, descriptions, images (Image Handler as Torvista mentioned), add USPS since you're in Houston, and you have all you need to sell product.
If your hosting allows it, keep a /_test folder going at all times. Normally your site would be in something like /home/YOUR_ACCOUNT/public_html. Crating /home/YOUR_ACCOUNT/_test with a clone of your site and a different database allows for testing those wannabe mods before taking them to the public_html main site. You can make it a subdomain of test.YOURSITE.COM for ease of access. It also allows you to test different PHP versions. Can't do that if the _test is in the public_html folder. Being "Above the Root" and starting with an underscore eliminates the possibility of being accused of duplicate product.
After that, it's prioritized by your particular business' needs. Do you need to do regular changes to prices? Are there just a few products to change or a few hundred?
Do you have a lot of orders that are incorrect in some way? Maybe you would want something like Edit Orders. But, that's a complicated mod to maintain through upgrade and as Torvista said> The more you modify, the more work you will have on the next upgrade...so don't fix what isn't broken.
One of the extras we do add for the customer's benefit is Instant Search. It helps the customer get where they want to go quicker.
And, as far as your browser, make sure you bookmark the forum. We're here to help.