When it comes to said, I tend to use it a lot when I actually say people are talking. I do try to avoid it repeatedly like:

"Hello." Bon said
"Hello." Etho said.
"Good morning." Tyler said.

I would try to do something along the lines of:

"Hello." Bon said with a prideful look and a boastful tone.
"Hello." Etho answered irritantly, his anger at Bon still very obvious from the actions of the previous night.
"Good morning." Tyler sighed, knowing that this was going to be a long day with the tension between his two friends.

I try to avoid saying said repeatedly but I do tend to use it a lot. However, it does help if you add in tone in such to differentiate. Also, I occassjonally, if only two people are talking back and forth, I sometimes won't even say who is talking because I've specified previously who is speaking so it'll be like:

"Hello." Bon said.
"Sup?" Etho replied.
"Nothing much. Just chillin."
"Oh really? Cause it looks like you're plotting something."

As long as you don't use it repeatedly like every time someone speaks I'll think it's ok, but it helps to transition to create variety. Keeps people interested.