If you're going to use mouseovers, it's best to use only mouseovers. Introducing multiple targets will frustrate you more often than it does what you intend, because of the way <t> works with heals -- basically any line after <t> won't matter, because once it gets to <t>, it will heal "someone", and "someone" will usually be yourself if you're not targeting a party member.
Also, avoid using models as mouseover targets. Party frames and target frames are the way to go.