First, I like the filioque because it better reflects scripture. I say better because I am comparing to the admittedly older version of the Nicene-Constantinopolitan Creed which said simply of the Spirit that he proceeds from the Father (τὸ ἐκ τοῦ Πατρὸς ἐκπορευόμενον). Luke-Acts teaches that the Spirit could not indwell the church until the risen Jesus ascends to the right hand of the Father and is glorified. Pentecost is a royal announcement and a Joel-invoking outpouring of Spirit new-creation power upon all flesh until he comes. It is the risen Son that pours the Spirit out upon his people. And the Spirit that he pours out is not its own but mediates the Son; Paul goes so far as to call the Spirit the Spirit of Christ (πνεῦμα Χριστοῦ).
Second, I think that the filioque closes the door on a second door of salvation, namely the mystical pursuit of theosis by means of the Spirit alone. If the Spirit proceeds to the church from the Father alone, then there is an avenue to the Father apart from the redemptive work of the Son. As I read it, the Spirit is always working through the Son toward theosis with the Father. And to say that one can work without the other is to tip the scales into either modalism or tri-theism. Moreover, Neo-Platonic contemplation has been part of the tradition of the church since Origen wrote in Alexandria. We still have Mount Athos today. We still have the pneumatic-centrist fervor of pentecostalism, and the "still, small voice" private revelation of American evangelicalism. So lest we give ground to an old temptation, I appreciate the stopgap that the filioque affords.
And third, I think the filioque reminds us that revelation is soteriological not metaphysics. As I said, the creeds are not theologies of glory but theologies of the cross. It is not ours to climb up and behold the naked God. The addition of the filioque to the creed, to my mind, is a necessary soteriological correction. But, then again, I like my christology at the center. And this leads to my last point.
My last point is about Trinitarian theology itself. My understanding is that one of the most important ways of differentiating the persons of the Trinity is by their origins. The Father is uncreate. The Son is eternally begotten. The Spirit is eternally aspirated from the Father. The Son and the Spirit eternally proceed from the Father, but not in the same way.
Therefore, if we remove the filioque, aren't we muddying the waters? If we remove it from the creed, then no differentiation is made about origin. (This is assuming the creed is a metaphysical statement, even though as I said, I don't see it that way.) The loss of clarity is at least unhelpful. Why would we want to do that? Indeed, why not amend the creed again to be more specific about origins?
I'm not a fan off innovation, or of keeping theology modern for modernity's sake. Nevertheless, for these few reasons, I like what the filioque is doing. Let's not be too hasty to throw it out.