I don't think Blizzard will have a problem with it taking a year to reach Level 25 in a guild of 10 people... They are perks, not necessities,
It can by psychologically frustrating that others can get the perks faster, but if something cool is added to a class you don't play, do you complain about it, or just accept that it's an update not that relavant to you? The same applies here... The daily cap means you take twice or three times the time, instead of 20 times the time of the big guilds, so it's a good thing for smaller guilds that the cap is there, but I think you'll just have to accept that you will get the perks slower - or find more people to join your guild, if that's preferable to keeping your tight-knit group, in exchange for nice, but not necessary, perks...