Wulfos has alot of good advice. So i'll just build a little on that.

Cahange the invite macro on your main and it will save you a macro. Push it once for an invite then again for them to accept group.

/script AcceptGroup();
/script AcceptQuest();
/script AcceptTrade();
/script RetrieveCorpse();
/script RepopMe();
/inv jusab
/inv jusac
/inv jusad
/inv jusae

Here is my focus macro. It also serves as a follow macro to save space. It allows you to swap mains quickly when one dies/MC and alows you to pick who you want your main to be.

/clearfocus
/focus Jussa
/focus [modifier:lalt] Jusab
/focus [modifier:ctrl] Jusac
/focus [modifier:shift] Jusad
/focus [modifier:ralt] Jusae
/fol focus

Shared healing gives you the fastest heals and powerful renews. But to be quick about healing it's best to have a key for each toon, and then one that you can use to target anyone else you may group with.

#showtooltip
/cast [target=jussa, modifier:Alt] Flash Heal
/cast [target=jussa, modifier:Ctrl] Power Word: Shield
/cast [target=jussa, modifier:shift] Heal
/cast [target=jussa] Renew

#showtooltip
/assist focus
/cast [modifier:alt] Flash Heal
/cast Renew

What good is 3 fears at the same time? you will want to cycle them.
Play with this till you get it working for 3 guys cause i use it for 4/5. each is diferent for each toon, change the coma to fit when you want to fear.

#showtooltip
/castsequence reset=30 , Psychic Scream, , ,

#showtooltip
/castsequence reset=30 , , Psychic Scream, ,

#showtooltip
/castsequence reset=30 , , , Psychic Scream,

Try to package as many spells as you can to the same key. Mainly to save macro space, but it helps to eep things close at hand too.

#showtooltip
/cast [target=focustarget, modifier:shift] Vampiric Embrace
/cast [target=focustarget, modifier:ctrl] Vampiric Touch
/cast [target=focustarget, modifier:Alt] Devouring Plague
/cast [target=focustarget] Shadow Word: Pain

Welcome and good luck.