I am sure everyone has their opinion as to what makes a good vacuum level. I definitely have mine. I agree that G4 comes as close to a perfect vacuum level as any I have seen. Even on TC, you are never really that far from an oxygen recharger. However, when having to constantly search for, or run back to the recharger, becomes the overwhelming priority on the level, then the level ceases to be fun for me. Two examples that come to mind are Scott Noblitt's "Lack of Oxygen" from his scenario "Escape!!" and his "Reminds Me of a Hoover" from his scenario "Escape 2". I simply did not enjoy playing either of those levels. I did manage to get through both on TC, and was even able to vid the first one. But in both of those levels, i found that there was BARELY enough oxygen to finish either level. (BTW Scott, please don't take offense at this...I thoroughly enjoyed your scenarios....just not those two levels.) I understand your feelings Steve, and I did have to come up with a viable strategy for both levels. But I simply did not find either level entertaining at all. To me, the perfect vacuum level is one in which having to return to the recharger falls more into the category of a "nuisance". In the perfect vacuum level, I am going about my business of fighting the Pfhor, while watching my oxygen level, until at some point, I have to cease what I am doing, run to the recharger, and then return to what I was doing. But when the lack of oxygen becomes SO critical that fighting the enemies of the level begins to take a back seat, and the overwhelming and constant priority becomes running back to an oxygen recharger, or finding another canister, then the level ceases to be fun for me. Don't get me wrong, I do expect the lack of oxygen on a vacuum level to be enough of a nuisance to cause me to change the strategy I use in completing the level. But one CAN do that and make the level fun at the same time. IMHO
As for Acme Station, this is simply a level in timing. Nothing more. As far as I am concerned, there is no skill involved in winning this level. You really do not have to fight any of the enemies to finish it. It is simply an exercise in good timing, dodging enemies, and LUCK. Was it a fair level? Perhaps not. Remember though, that if you visit the secret level "Carroll Street Station" first, you can enter Acme Station with 2x shields, making the level much easier. It certainly would have been more fun with an oxygen recharger located somewhere on the level. I never will understand how someone can have a vacuum level with terminals and NOT provide the player with enough oxygen to read the terminals at their leisure. In defense of Post Naval Trauma, let's remember that the level does provide an oxygen canister and PB at the very beginning of the level, as well as a Fusion pistol.
BTW Steve, the scenario "Operation Vengeance" was Mark's....one of the best :)