You could add a single unupped Nova and an upped Protect Artifact if you don't want to replace the Mark. This also opens up the possibility of using an upped Purify - with the boost it's getting next update, it will provide defense against poison AND a little extra regen otherwise.
Not saying you turn this into rainbow... but entropy does have novas. If you're having trouble holding onto that Electrocutor, it's an option.