Is it worth adding a Viltrox 56mm 1.7 + 25mm 1.7 to my 35mm 1.7, vs just a Sigma 18-50mm 2.8 for a6100?

I've got an a6100 and picked up a Viltrox 35mm 1.7 and was blown away by how much better it looked compared to my Sony 16-50 3.5-5.6 kit lens, especially in lower lighting like the shows I was photographing. I've also appreciated the way a prime lens forced me to be more intentional and active about my composition instead of just fiddling with the zoom from one spot.

My question is if it's worth rounding out a prime lens trio with a 56mm and 25mm, which with the 35mm I already own and APS-C crop factor means I'd approximate the classic 35mm/50mm/85mm trifecta, and with the Viltrox lenses being under $200 I'd be under $600 all in for the trio. Alternately, is the Sigma 18-50mm 2.8 really as great as the hype? I'd lose a bit from the top end, gain a little at the bottom, lose some aperture, and be out $500+ for the single lens.