Learn C++ template-linking magic well enough to be able to build a working shared library.
Design a language for expressing flow attributes, and build a parser to read that language, so that attributes can be specified in a configuration file.
Build an autoconf wrapper for building ANTARES.
Set up the autoconf wrapper to be able to build on *BSD.
Tidy up the dependencies and depended-upon libraries (particularly qcap - the reliance on a patched pcap for file pointers is not a great thing).
make certain that all attributes update when their values are accessed, otherwise bad things _will_ happen. This would be best to do by changing the getAttrib handling so that the superclass was more involved, possibly by replacing the per-attribute function with an initialization that populates a member which could be accessed by Attribute::getAttrib.
Find a better way to implement stateful packet filters.