I'll start off by saying that I dislike gimmicks in games. By gimmick, I refer to a mechanic of any general incentive that was made with the intention to extort you into playing for longer periods of time. Achievements, stars in games like Angry Birds, and even special tokens or something in a platforming game. These are things that don't impact the gameplay or deepen the experience-- they solely exist to entice the player to keep on playing.
In a way, I see it like adding sugar to fruit juice. The juice has it's own natural sugar, but the producer adds in more sugar to entice you into drinking more and to hook you on it... So that they can sell more juice! It adds no nutritional value, and it is in fact quite unhealthy.
At this point, when I go to play a game like Angry Birds, I simply ignore achievements and stars. Thankfully, they don't inhibit the experience(unlike the unavoidable added sugar) so I can ignore it. It doesn't "break the deal" for me, I can look past it and still enjoy the game. And it's not like I'm not an offender of this criticism either, I've certainly made pointless gimmicks in my games before.
The main issue here is, to reiterate, that the gimmick doesn't really do much to add value to the game or add to the experience. It's just there to hook you, like sugar. That's what I dislike! I dislike that kind of extortion which only serves to get you to play more.
Going back to the fruit juice comparison, some game developers even refer to watering down their juice so that you have to drink more to get the same amount out of it. That is also a big no-no for me, for the same reason. That is a deal-breaker for me, when the tacked-on extortion actually gets in the way of and interferes with my play experience.
And now that brings me to my second idea: Designing with a Goal.
Just like probably any piece of art, you design around a goal. One central idea you want to emphasize, or one outcome you are aiming for. Mario is about platforming, Zelda is about saving the world, Call of Duty multiplayer is about competitive engagements. Some games have a less concrete or clear goal than others, such as Zelda I'd argue. But the general point is that in some form a game is usually designed with a goal in mind.
As a designer, I've found that designing with a clear goal or theme in my mind helps me create, overall, a much more coherent experience. And I am not saying that you define limits for your game or narrow your focus, deciding to only focus on one core mechanic or idea. I'm talking about having one overarching idea that guides the vision for how you design your game. For instance, with Z4R, the overarching vision is to create a game that's focused on precision, thoughtful play, and having great touch controls. It's not about limiting your vision, it's about directing it.
And also, as a big fan of games, I've had a ton of influence from the games I've played-- for better and for worse. Many times I have included things in my game that do not fit my goal for the game. I included them because it seemed like 'convention' and because it's just something you do to make a more complete game, or I dare say, because it sounded 'cool'. No! I was making gimmicks which were bad in the original games in the first place. I was playing by convention and not evaluating my influences to see if they fit in with the vision I had for my game. They didn't.
I didn't want to create a game that extorted the player into playing more and more. Because my goal wasn't to hook them for hours on meaningless things, my goal was to create a deep and meaningful experience that was constructive and coherent. It wasn't like I needed to hook them for long periods of time to sell subscriptions.(*cough cough* WoW) My goal in mind was not to sell my game and loot my playerbase. It was to make a solid, 'legit' experience first and foremost.
And that is always the overarching goal in mind when I make games, to make a legit, awesome experience. At the very least, that is what I try to do. I have to be careful sometimes not to lead myself astray with conventions. I am an offender. You, if you're a designer, have also probably been an offender at some point. The idea is to make everything you design in your game 'matter' in terms of your overall goal. Directly or indirectly.
Design with your goal in mind.
Design with vision.
Design with integrity.
Much of the thought in this post was sparked by reading Adam Saltsman's post on "Contrivance and Extortion", so do go check that out as well.