Just thought being the OP I would share my observations , I have TI Flats on one of my basses and Labella (extra light gauge) on another, these are both short scale basses.
Using both basses at rehearsal I would actually say that TI's are middy with slightly less lows than some flats rather than bright, boosting or cutting mids made significant impact to the tone of these strings, these are not a string where it is useful to cut lows. Despite TI's reputation as being bright flats I actually found that boosting treble made relatively little difference and more than anything just introduced more noise into the signal.
The Labella's I would say are less prominent in the mids but actually ime seem to have more treble detail and boosting or cutting the treble made significant difference to the tone, strangely the Labella's actually strike me as being brighter.