Like most, I have always started off and ended up developing my game projects with intermingled core and game specific code. Why is it that I never realized until now that a game engine allows the best jumping off point? A conundrum?... seems likely.
Who the heck wants to either a.) start from scratch again and again or b.) piece meal code from other projects every time you start a new game project. IMHO (b) has to be one of the many reasons game projects fail in the initial stage.
That aside, the only personal drawback is that an engine requires something to drive it so if you used to getting something up on the screen ( game specific ) pretty early, it can be kind of tough when after all your coding the engine does nothing worthwhile ... yet.
And of course I still have a list as long as my arm of features, must haves and wants to implement and I'm sure I'll never be satisfied either. The beauty of it all is that once it's coded and tested it's done and you can always expand and update the technology at any time. I'll be glad to get over that hump, trust me. As far as my planned game, I'm just focusing on what I need to drive the fighting game specific code.
On a side note but related, I finally broke down and started to use Doxygen ( yep..I'm late to the party. I know). Doxygen has been something I've wanted to take advantage of for a few years now but always put it off. After spending a couple of days with it I'm hooked and cannot see myself without it. The class hierarchy and call graphs alone are worth the minimal effort to get it up and running. It's funny how much more of an understand you get about the code that you yourself have written! This will pay dividends and serve as decent road map considering that I'm hoping to focus on just game related code for future projects based off this current engine. To be able to peruse the Doxygen generated doc versus the traditional comments will really help to re-familiarize the brain if and when I start to add to the engine again.
Before I forget ... the art work. I'm such the consummate perfectionist, this behavior is also a cross to bear as well and is causing a serious creative block ( no I'm not making excuses). It's starting to sound like broken record but sketches, ideas and semi finished game related artwork is forth coming. Really...I'm not kidding ?
Damn... the second half of the year is upon us Monday. Time is flying and I still feel like I haven't come close to accomplishing the goals set fourth for the year (Depressing).