If I might throw in an opinion. On your secondary protection, if they are digital phones, use low voltage protectors. If your using analog phones or any type of regular ringing voltage you can't use them, like on an outside bell or something. Lastly bond all grounds together, this is the best thing you can do to keep power surges and lightning from jumping to a different ground potential. You will find differences of opinion on common bonding, but I've found this to be highly helpful in preventing problems.

Retired phone dude