But then you have an issue with someone completing level 2 requirements before finishing all the level 1 achievments. Rare events might be missed, and progressive ones would suddenly all unlock at once.
Frankly I'm no fan of the level tiers or the simple play-to-earn ones like kill X players with weapon Y. I'd prefer the achievements be rooted in epic Goldeneye moments, so a player's achievement list shows what the player has experienced. The play-to-earn things I'd reserve for awards. I.e., an achievement for earning Most Deadly 50 times.
Your formula can easily be simplified to "do X, Y number of times", which would then make your suggestion for a achievement void. How about getting ideas from achievements on other games.
Some simple ones I thought of are:
Arms Dealer - Touch every weapon in the game at least once.
Traveling Tourist - Win a game on every map at least once.
Ghosts Are Real - Go a round without using any weapon and without getting killed.
Manhunt - Kill X amount of people without dying.
Helping Hand- Play in a game with X or more players from your friends list.
Genocide Leader- Accumulate X amount of kills overall.
Caveman Warrior - Break all the monitors/computers in Bunker.
I'm sure there are thousands more people can think of, but I agree on the basis that "kill X players with weapon Y" would get boring.
-EDIT-
The Achievements don't always have to be positive either. Some examples would be:
Playing With Guns - Kill a member of your team.
Suicide Bomber - Kill a enemy and your self with an explosive.
Traitor - Kill X amount of people on your team.
