I suggest getting yourself a mithral/darkwood buckler, magically enhanced. It will help out your AC, is cheap, and you won't incur any real penalties due to no ACP.
Make up a few different spell lists, ie: dungeoncrawling, off-days, wilderness, planar adventure, etc. Switch it up a bit, as variety is your bag.
I'm not sold on the effectiveness of turning a Spirit Shaman into a summoner beyond investing in the spontaneous summoning, ymmv. I think having a few metamagics might behoove you, since that is the real benefit of the retrieval system for spontaneous casting, in my opinion.
If you really want to summon as your focus, without being an actual Druid, consider dipping a PrC that gets you the Summoner domain and going Malconvoker. I believe with the way adding domains to non-clerics works, you could retrieve Summon Monster whatevers and cast as many times as you have slots. Just a thought to consider exploring, especially since you are a CHA-based caster.
Also, don't forget to Spellstaff your quarterstaff.