Although It's a shame that Ground Zeroes' main mission can be beaten so quickly (especially with veteran mgs players) at the same time It's a game that die hard fans can really appreciate because it will get us prepared for Phantom Pain, but also will give us a fix until it comes out.
There are many things to do in Camp Omega once the Ground Zeroes mission is completed. Some missions being harder than the main mission itself.
With the strategy that you need to actually execute these missions properly as well and get the best ranking, combined with the hidden items throughout the base and other unlockables, there are plenty of reasons to keep heading back to Camp Omega well after your initial playthrough. At the same time, it has potential to be the most challenging and rewarding MGS in the series. (along with Phantom Pain I'm sure)
Gameplay is excellent, graphics are excellent, and Kiefer actually did a great job. It could have had a little more story to it but that's my only beef with the game. I recommend it to any MGS fan or stealth action fan for that matter. For the price, there's alot of fun to be had here.