I've been working on some custom fishing rods/devices that utilize the four responses that the invisible rods send on chat (and the linkmessage channel, for one custom application) but I was thinking, it would be great if there was also a message that we could capture, for levelling-up.
Maybe format it like the rarity message, i.e. "level n" where n is the level number the avatar has just attained. That would allow some custom reactions (animations etc) to be performed on levelling. It's doable now by setting a listener on channel 0 locked onto the avatar's rod then parsing the strings for the levelup statement, but it'd be easier and faster to keep everything on the same special chat channel / linkmessage channel, and the same format.
Anyhow, just a suggestion for future version.
Cheers!
-Atashi
p.s. if this were implemented, then it would be nice if the 'quiet' catch mode also suppressed the normal level-up announcement.