SfLogicNinja, who does YouTube videos mostly about using Logic, did a masterclass sponsored by Remix magazine about making dance tracks in Logic, but there's also useful info in it even if you're not using Logic.
http://remixmag.com/remixhotel/sflogicninja_class1/
One of the first things he mentions is pulling all the faders down to -20dB to -12dB when you start out, so you have plenty of headroom. Concerns over loudness should be handled by the mastering engineer. It's easier to get a higher quality master out of something with more headroom than something that comes to the mastering engineer already squashed.
After seeing that video, I began reading
Mastering Audio: The Art and the Science by Bob Katz, and the author agrees. As a mastering engineer, he wants to see mixes with a relatively low RMS volume and peaks no higher than -5dB. Basically, once you go above this, you are in danger of adding unwanted digital distortion to the mix. (This is assuming 24bit recording. I'm not sure, but I believe he's okay with peaks that go above -5dB if it's 16bit, and I'm too lazy to look it up right now.) What it comes down to is that you can always squash the life out of a mix, but once you do that, you can't really go back.
So yes, the Access Virus TI, when used as a plug-in instrument, tends to peak at about -18dBs in a DAW; however that is not a "flaw," for the reasons pointed out above by marc and others. The whole "everything must be at zero" thing is just a symptom of the Loudness Wars, which is a mastering thing and not a mixing thing. When you compose and mix a track, you want headroom; once that is done, you can worry about the total and absolute loudness. When you want to share a track on the internet or with your friends, yeah, you'll probably just want to take your final mix, the one with plenty of headroom, and then use compressors/limiters/multipressors/maximizers/finalizers etc... to do a quick and dirty "mastering" to "louden up" your track - but keep that unsquashed mix for the day that you can afford getting it mastered by a real mastering engineer and that will make a world of difference for the final output.