Superheavies a "necessary evil"?! I don't know about you guys, but for me the chance to use legendary units is what excites me the most about apocalypse. Titans, superheavy vehicles and gargantuan creatures are just far too cool to not use, and what is apocalypse all about if not awesomeness?
I suspect that the main problem with these units at the moment is that they have just been introduced into the game and no one really knows how to deal with them. I think that their advantages and weaknesses will become apparent once people start having more apocalypse games. People will figure out what a good balance of superheavy to normal troops is. If it turns out that all superheavy is usually the best choice strategically, then the rules will have to be revised. I doubt this will happen however.
As long as everyone is aware of how superheavies work before the battle and build their armies accordingly they should be plenty manageable. For example, you can't rely on glancing hits to do much of anything against them so us Nid players will pretty much NEED to take gargantuans. Luckily, hierophants and hierodules can unleash torrents of str10 ap3 firepower all while moving 12 inches and tearing hoardes of infantry to shreds with their stomp attacks. If you don't have the models, get some or convert them and use a tissue box or overturned bowl with "Hierodule" written on the side of it in the mean time.
Think about it, wouldn't it be foolish to not take any anti-tank/monstrous creature weaponry in 40K? Apocalypse is the same except it introduces another level of power. Both very infantry heavy and very tank/monstrous creature heavy armies are possible in normal 40K they perform very well when your opponent isn't expecting them, but each has glaring weaknesses that can be easily exploited by a good opponent with a balanced list. I would imagine an all superheavy list in apocalypse would be very much like a godzilla list in 40K: very scary to look at, but easy to take take down if you keep your cool and know what you are doing.