While the editors are a good guide to 'eras', other things to consider are owners, the malign/benign influence of the sub/assistant editor (such as McKenzie and Diggle) and those sudden imposed changes/effects of available artists/writers - I would divide 2000AD into the following:
1-85 Pretty dire period really. Only Dredd (of which a lot of is rubbish - see most of the Luna-1 stories) and Robo-hunter really stand out. The rest is fairly forgettable.
86-126 The superior Starlord merges and suddenly the comic is improved no end with the inclusion of Ro-Busters and Strontium Dog.
127-177 Oh dear. Tornado bites the big one and all the good work goes down the drain, as 2000AD is forced to take on BlackHawk and Wolfie Smith (Dave Gibbons later redeems himself with The Watchmen - just!).
178-307 The "Golden Years" part 1. despite the odd early hiccup (Mean Arena, Meltdown Man), this was a period where 2000AD really consolidated what it did well. The Wagner/Grant writing partnership starts and dominates the comic for the next 400 Progs. The best of the oldies return (Stront and Slade) while classic after classic start - Nemesis, Ace Trucking, Rogue, Slaine.
308-499 The "Golden Years" part 2. Alan Moore's tenure as a writer of multipart thrills, combined with Wagner/Grant and Mills at their peak create some of the best comics ever...
500-588 The "new wave". Moore leaves, but 2000AD trundles on regardless. Replacements start to emerge in the form of Milligan, Morrison and Smith. The Wagner/Grant writing partnership ends.
589-722 Crisis! At this point, someone takes their eye off the ball - Ezquerra and Mills go with disasterous consequences - Mills work on Crisis will colour much of what he does from here on in with an overly preachy tone, while Alpha is killed off in the absence of the Moustachioed Maestro. The new wave fail to fill the gaps left by Moore, W/G and Mills, many using 2000AD as a springboard to US comics. The launch of the Megazine and Revolver further stretch available talent.
723-937 Disaster! Wagner, Grant and Mills set up their own rival with Toxic!. 2000AD tries to fill the gap with Mark Millars Robo Hunter. The darkest days of 2000AD...
938-1199 Slowly the comic tries to rebuild itself from the ruins and that bloody film! New writers Abnett, Robbie Morrison and Rennie help bring a little consistency to the comic, with lasting characters like Dante and Sinister Dexter. This is more from the commitment of the editorial team than the publishers.
1200 to present. Rebellion give 2000AD the attention it has long deserved. Still a long way to go, and until the next Alan Moore comes along, still not perfect, but definitely on the up (just give over with the smut, OK?).
1-85 Pretty dire period really. Only Dredd (of which a lot of is rubbish - see most of the Luna-1 stories) and Robo-hunter really stand out. The rest is fairly forgettable.
86-126 The superior Starlord merges and suddenly the comic is improved no end with the inclusion of Ro-Busters and Strontium Dog.
127-177 Oh dear. Tornado bites the big one and all the good work goes down the drain, as 2000AD is forced to take on BlackHawk and Wolfie Smith (Dave Gibbons later redeems himself with The Watchmen - just!).
178-307 The "Golden Years" part 1. despite the odd early hiccup (Mean Arena, Meltdown Man), this was a period where 2000AD really consolidated what it did well. The Wagner/Grant writing partnership starts and dominates the comic for the next 400 Progs. The best of the oldies return (Stront and Slade) while classic after classic start - Nemesis, Ace Trucking, Rogue, Slaine.
308-499 The "Golden Years" part 2. Alan Moore's tenure as a writer of multipart thrills, combined with Wagner/Grant and Mills at their peak create some of the best comics ever...
500-588 The "new wave". Moore leaves, but 2000AD trundles on regardless. Replacements start to emerge in the form of Milligan, Morrison and Smith. The Wagner/Grant writing partnership ends.
589-722 Crisis! At this point, someone takes their eye off the ball - Ezquerra and Mills go with disasterous consequences - Mills work on Crisis will colour much of what he does from here on in with an overly preachy tone, while Alpha is killed off in the absence of the Moustachioed Maestro. The new wave fail to fill the gaps left by Moore, W/G and Mills, many using 2000AD as a springboard to US comics. The launch of the Megazine and Revolver further stretch available talent.
723-937 Disaster! Wagner, Grant and Mills set up their own rival with Toxic!. 2000AD tries to fill the gap with Mark Millars Robo Hunter. The darkest days of 2000AD...
938-1199 Slowly the comic tries to rebuild itself from the ruins and that bloody film! New writers Abnett, Robbie Morrison and Rennie help bring a little consistency to the comic, with lasting characters like Dante and Sinister Dexter. This is more from the commitment of the editorial team than the publishers.
1200 to present. Rebellion give 2000AD the attention it has long deserved. Still a long way to go, and until the next Alan Moore comes along, still not perfect, but definitely on the up (just give over with the smut, OK?).