The revised Hallucigenia looks pretty much like a spiky version of an Onycophoran or velvet worm. In fact a quick 'google' shows that they are generally believed to be related to the Onycophora.
How different are the Burgess Shale fauna in terms of topology? I can't think off hand of anything really radical in terms of deviating from the tube with a mouth and optional anus.
TTFN,
WK