Woodcutting hasn't recieved much new content lately, so i'd suggest bringing in a tree and new axe.
One of those is ivy, grown on walls, not rewarding logs when being chopped.
For example on the locations runescape has them aswell, varrock castle, falador etc.
Maybe remove crushed nests from magic tree's and replace them when chopping ivy or reward players with unknown stones small % chance on recieving them (which can be
handed to the varrock museum rewarding players).
Next up is infernal axe, i've seen this being requested in both Emps' scape & world. The axe has 1/3 chance to grant firemaking exp on cutting.
The infernal axe needs a smouldering stone being used on a regular dragon axe. The stone could be a reward from any boss who is lacking attention at this moment.
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Maybe there is also a possibility to add the: dragon harpoon, and dragon pickaxe. Which both can be upgraded with a smouldering stone into the Infernal harpoon (1/3 chance on cooking exp when fishing manta's (?? new fish type) and infernal pickaxe (1/3 chance on granting smithing exp).