Sounds like a pretty solid foundation to build upon - and definitely the right approach to start basic with such a complex game mechanic (no need to tear down and rebuild it, just build upon it).
Time frames for decay also sound fairly reasonable. Initially I was against the idea of a fuel system, but if it's fairly easy to get to max fuel using basic easily obtainable materials, then I don't see too much of a problem here. I also like the idea of adding progression into fuel sources too, so you can extend the decay time.
I'm definitely in favour of this! As mentioned in another thread, if you leave the game for an extended period and for whatever reason are not able to fuel your beacon, you shouldn't be punished for it - I think a lot of returning players would be deterred from playing, having to start from nothing again. Maybe add in some mechanic where you need to do a set of tasks on behalf of the Central Guild, just to get your stored stuff back - like a payment for holding services rendered!
Also in favour of having information about all of your beacons fuel times available from any of your beacon controls - I know lots of players that have beacons spread across many planets, so a central source of just information would be very handy, to allow you to see when and where there are expiring beacons.
This is only an issue at present as people have become accustomed to hiding the ugly grey block with the world 'BEACON' emblazoned on every side of it. When it has it's lovely new functional mesh and textures, you may not want to hide them away so much!
Personally I am against any player voting system, as I see this as just another tool for griefing, albeit on a larger scale. You'll just end up with large groups of players preying on the weaker/smaller groups and lone players - effectively bullying them out of their enjoyment of the game - or off of a planet so that they can be the unopposed capital city. Not something I want to see.
An automated system would be much better in my opinion - that way, the same rules apply for everyone ... and the less ways to abuse the system, the better.