The few things that help:
Accept all macro:
/script AcceptQuest();
/script AcceptGroup();
/script AcceptTrade();

There are WAY more things to put in it, but I don't have it at work.

The next part is auto-accept quests on your alts. I used Multiboxer v2. It auto-accepts quests that your main shares (accept quest on your main and then share it). Jamba now can do that, but is kinda clunky in that you can't only accept quests from your leader, it is either all NPCs or none. But it will auto-accept escort quests which helps.

The easiest way is to get the quest on your main and then share with alts and push accept macro. But that doesn't fix talking quests or rewards.

To talk to NPCs, you can use a keybind for "interact with target". You can select the NPC on your main, push your assist button and then interact key, you can select options that are broadcast due to either Multiboxer or Jamba. Jamba has an option to either accept rewards based off main (get same reward) or to let you pick on your alts.

Hope that helps and good luck.