Heh, oddly enough, the RCT can probably be better thought of as a way of explosively _decompressing_ a glider construction recipe. There are lots and lots of reasonable-sized recipes for constructing different patterns. When you apply the RCT trick to any of them, the cost in gliders always shrinks to 15, but the pattern's bounding box always expands to something gargantuan.
The Life pattern that most evokes DNA and self-replication is another megapattern from several years ago, the 0E0P metacell, which even has a visible "nucleus" for its "DNA":
Equally, compression, is this an avenue worth exploring and a whole new way of doing things awaiting to be tapped?