I owned some Wal's and even a 4 strings fretless MKI in the early 90's that I bought back twice as I loved the totally unfaithful and unclear sound coming out of this bass.
The Wal has a unique sound that you like or hate, but it's certainly not a clear one thanks to the pickup(s), but can be tweaked so much through the filters based preamp that you might think it's clear. And to add some fun to this, it can become a real nightmare live or in the studio if you or somebody touches the knobs by accident.
To get back to clarity and sound as a Wal pickup is a humbucker it senses the string at two different points, hence creating some phase cancellation, so absolutely not a clear sound. Furthermore, there's some crosstalk between strings as the mini humbuckers per string are then wired in parallel at the output, so the other strings magnets do sense the adjacent(s) string(s).
An Alembic or a Leduc with the dummy coil and full single coils pickups has a real clear, precise and defined sound. And if you like the filters based preamp then go for an Alembic. It will be clear, with the less possible crosstalk thanks to the low power magnets used in the single coils pickups.
I do love both sounds, but they are, strictly speaking, totally opposite and mismatched a lot according to what I'm reading here.
Clarity and absence of crosstalk also come from your playing technique and your ability to mute the unplayed strings...