"Such analysis is challenging because it is high-dimensional and sparse**:** however; the result can be more useful and informative."
I do agree with Luke that one of the options he mentions is probably the appropriate one to use.
In addition to those you mentioned, the Oxford Dictionary gives us:
nevertheless, nonetheless, still, yet, though, even so, for all that, but for all that, despite that, but despite that, in spite of that, but in spite of that
anyway, anyhow, be that as it may, having said that, notwithstanding
even so, howbeit, nevertheless, nonetheless, notwithstanding, still, still and all, though, withal, yet
Words related to however
after all, anyhow, regardless