For your football viewing experience, at Etihad Stadium (Docklands) you get what you pay for. The lowest priced seats are often little better than watching the game at home, whilst the premium seats offer a commanding view of the game at the perfect angle for seeing both team strategy and on-the-ground action.
The roof is closed most of the time, so weather is generally not a factor when choosing a seat. If the roof is open, be mindful that the eastern (Coventry) end of the ground will be facing into the sun in the last quarter of the game.
Most visitors to Etihad Stadium will be tempted by the least cost ticketing option (general admission). If you're there early, this is the best option. You should move quickly to secure your seats on the ground level. Don't sit right on the fence because the surface of the ground at Etihad Stadium is curved and the players' feet get chopped off from view when they are on the other side of the oval. About five or six rows back from the fence is ideal.
If you buy general admission seats and there's a large crowd already inside, you might as well tear up your tickets and go home. After the ground level seating is full, you'll be forced up to the third level. You'll need to bring some climbing ropes to reach these high altitude seats, as well as a pair of binoculars to see any of the game close up. If you want to see who kicked that last goal, your eyes will be straining to see replays of the action on the tiny television boxes (not flat screens) that are suspended even higher in the air than you are. The giant scoreboards at either end of the ground are too far away to see properly.
If you can afford it, the premium seats on the second level are fantastic. You are high enough to see from above where the players should be positioning themselves, but still close enough that you feel they might actually hear you if your instructions to move are yelled loud enough.
For the most part, watching footy at Etihad is overpriced and a less rich viewing experience than the other main ground in Melbourne, the MCG. If you can, wait until your team is playing at the MCG. If you're a football addict or only in town briefly and can't wait, get there early or open your wallet wider to get the most out of the game.