I have Zeta and Synthmaster, both great synths.
I tend to use zeta for reeses and traditional synth sounds, because of it's really great sound. It's FX are decent but a bit limited, so i usually end up using it for its 6 oscillators and good range of analog waves.
Synthmaster is great for leads and pads, but i dont tend to use it much because i have a pretty poor workflow with it, and its complexity takes a while to get used to making sounds.
When it comes to making bass sounds, envelope modulation is a tried and true way of getting a punchy moving bass sound. Both Zeta and Synthmaster have an assload of envelopes, and you can use them to modulate any parameter you think would sound good. Pitch and cutoff are very common and will give you quick results with any waveform, but you can also modulate resonance, wave-morph, distortion and heaps of others to get a good sound. Tweaking decay and sustain will give you variety, and you can automate throughout the track to give it more variation.