Please, make a unified set of game mechanic definitions!

Witness the endless arguments in 4e over what certain terms meant. Take attack for example. What did it mean? It sometimes meant an attack roll. It sometimes meant using an attack power. Make a defined set of terms and stick to it. It would really cut down on the ambiguity.
Sorry WOTC, you lost me with Essentials. So where I used to buy every book that came out, now I will be very choosy about what I buy. Can we just get back to real 4e? Check out the 4e Conversion Wiki. 1. Wizards fight dirty. They hit their enemies in the NADs. -- Dragon9 2. A barbarian hits people with his axe. A warlord hits people with his barbarian. 3. Boo-freakin'-hoo, ya light-slingin' finger-wigglers. -- MrCelcius in response to the Cleric's Healer's Lore nerf
the glossory section of the RC was a great tool for this, however some things needed less ambiguity. 

common arguments

- what is an attack? (power or attack roll)
- what is a "damage roll" if a power static damage power gets extra damage in the form of a die roll, does it now become a damage roll and you also gain the bonuses that only apply to damage rolls? 

so defining these things 100% would make things very simple for all players  
Yes. Clear definitions go a long way into making things better. Any mathematician knows that very well.

Define all your terms in an index, use keywords extensively to govern all kinds of effects and make the system more organic. Add all the rules for burning stuff under the Fire keyword - any kind of fire can be used to burn stuff except where specifically mentioned. Add all the rules for stacking bonuses under the definition of bonus. Don't fall into the Iron Heart Surge pit trap: if something removes "an effect" you'd better make sure it has a precise meaning and cannot be ruled to, say, suicide (remove life) or as a birth control method (remove pregnancy) or as a planar travel tool (remove need for air)...
Are you interested in an online 4E game on Sunday? Contact me with a PM!
Reflavoring: the change of flavor without changing any mechanical part of the game, no matter how small, in order to fit the mechanics to an otherwise unsupported concept. Retexturing: the change of flavor (with at most minor mechanical adaptations) in order to effortlessly create support for a concept without inventing anything new. Houseruling: the change, either minor or major, of the mechanics in order to better reflect a certain aspect of the game, including adapting the rules to fit an otherwise unsupported concept. Homebrewing: the complete invention of something new that fits within the system in order to reflect an unsupported concept.
Ideas for 5E