Magic spells - mixed and redundant spells

Just an idea here, but one thing that I liked about the DnD based spell systems that PT/BG/BG2/IWD/IWD2 used is that they included a very wide and varied list of spells. Many spells were redundant with others, and some were extremely powerful while others were almost useless. This was in part because they were taken from the PnP game, but it wound up being a good thing for the CRPG.

The reason for this is that choosing your spell repertoire was not a simple matter of "get the best possible spells" but instead you had to evaluate and assess each spell, and maybe try them out in the game in order to determine which ones fit your playing style. This added to the depth, complexity, realism (well, sort of - it is magic), and overall enjoyment of playing the game. IMO that's the #1 weakness of all other games with magic - there's not much strategy or thinking required.

So my idea is this: start designing a set of of logical and concise spells, but then mix in some extra ones, maybe shuffle some things around, add some filler and redundancy and less logical ones. In other words, don't make it so perfect that everyone will strive for the exact same set of top spells. Then leave it to the player to discover what set of spells are the best combination. More importantly, see how different players pick the ones that they think are best.