I think the World Group should be every 2 years but I see the argument for an annual tournament for the lower levels (brings in revenue and publicity to countries where tennis may not be a high profile sport etc etc). Could it somehow be split with teams securing their place in the WG in each of the 2 years of an annual feeder competition for a WG held on a 2 year cycle? (that is, if you secure a place in year 1, you don't play again until the next WG event)
Think teams reaching the final 4 should get byes in the first round the following year if it remains an annual event.
Home and away ties contribute to the unique atmosphere and appeal of the event and feel this would be lost if the finals were at a neutral venue.
Every four years (at least WG, annually lower down would be OK for me as TO says) two after Olympic year, with Fed cup in other two years.
Also have real points on offer so the best players aren't effectively penalised for representing their countries. If the WG play more often I like TO's idea about the top teams getting byes. If we want to see the best players in it, then lessen their commitment to make it realistic for them.
I'm torn about the surfaces thing as it's a huge factor as home advantage, the trouble is if e.g. you get a clay tie in the the hard court season, the best players don't want to play as it will mess their body and game up for their next tournaments.
I like the best of five thing, it makes it special like Grand Slams. I love best of five tennis.
There has to be some changes to encourage the top players to take part.
I am not sure about points as it is potentially unfair to a good player in a small country if they are the only decent player and the country never progresses, equally if (like the French) you country is so top loaded that a top 100 player or even top 50 rarely gets to play.
Could possibly restrict the choice of surface to those used in ATP events at that time of year so for April hard or clay, July grass or hard etc.
Restrict players to only playing in 2 rubbers so can't have 2 man teams winning matches. May also help on committing top players so Andy knows he will not have to play 3 5 set matches in 3 days.
Final thought - if you really want to shake it up - combined mens and womens ties. 2 singles and 1 doubles each and 1 mixed doubles so 7 rubbers