There is nothing wrong with never taking a PrC, but I would advise you to soon decide which path Teleri will walk more in. If she takes up to 4th or 5th lvls in fighter, she can choose to spec in her goddess' chosen weapon, but I personally don't think she needs to go much further than that.
Higher end clerical spells and buffs will more than compensate for the BAB bonuses, and it will also continue to add depth to our healing capabilities. I truly think we are lucky that so far none of us have had to pay to be brought back from the other side, but I am not naive' enough to think our luck will last forever.