Ta da!
My I'm late to this discussion!!
Many many types of low pass filter - I can't really add any more to what has been said, you need to try them to see what works for you. The Moog one has a rich warmth to it which is great for Electronica, although I find its envelope resonance to be quite understated compared to others.
My 1st purchase from Moog would always be an MP-201, it is the glue that holds the bass in eletronica, from fat dub EQ settings to synth sweeps. No contest, don't look around, do not pass go, do not collect £200. Buy an expression pedal with it as well, connect it to cutoff and with the pedals you already have, you have got yourself an electronica set up.
I own another 3 foogers and an MP-201 and use them all in my live set up. I don't own the murf, although I have played with it. For LFO duties, you can either rely on good modulation effects (chorus and tremolo) after the LPF, or do what I and John Davis and Bond (Miloopa) all do, which is to connect an MP-201 to it and control the cutoff knob with a triangle wave or similar for huge sub wobble - this is however very expensive as a set up, and I do think that running a good tremolo after the LPF still gives great results.
Advantage of the MP-201, as well as it being the glue that holds foogers together, is that it accepts midi clock, so if you and a drummer play to a click, you can ensure your tremolo's are in exact time - as opposed to setting them up by ear.
As for a 2nd choice - The obvious second fooger to go for as an electronica bassist is the Freqbox as paired with the LPF is a monster for crazy noise and swells - however, it's not as versatile as I'd like and if I could bear to sell it (again) I'd prob fill it space quickly. I use the phaser as it's massive sounding and creates some stunning sub textures, but my real 2nd choice would be the ring modulator!
The Moog Ring Mod, on low settings is an amazing LFO an tremolo in itself, in fact it's the best tremolo pedal I've used on a bass... In its extreme settings the soundscapes it creates are amazing. It interacts great with other pedals and has become the Swiss army knife of noises on my board.
Hope that helps...
Shep