Weathered Wayfarer is a great add to mono white and will feel like Sol Ring if you have it opening hand. Note it says Land, as opposed to anything specific.
You have a lot of equipment tutors. Like, all of them I think. Widening your array of choices could help. Maybe consider Loxodon Warhammer for the option to gain life, Sword of Vengeance for a little everything, Sword of Light and Shadow is great as it protects Avacyn from the most common exile sources. Darksteel Plate may seem pointless, but Avacyn will be hated out some games and it could be a good idea to have a second way to try and push damage in through a board wipe. Obviously the former equipment is a lot better, but with all the tutors you can afford to play around and make sure they're really tested.
You may also want to add Trading Post. It can do a lot of work, most importantly trading in rocks late game for lost equipment.