I have what I like to think is a really good 52 point Kath Firespray

Kath with Expertise, HLC and Dengar.

I need some ideas for how to fill it out.

Thanks!

I'm running a bobaroo mindlink list with Ka'ato.

Try Manaroo with the Punishing One title. Give Ka'ato and Kath mindlink, and run Manaroo close to Kath. You'll have nice action economy, and a good number of red dice. You may have a few points left over that you can use to flavor to taste.

Dengar w/ title, Unhinged, and Lone Wolf. It's a lot of eggs in one basket, but it's a big basket and the eggs are grenades, and the basket is on fire, and ohmygodwhyistheresomuchfire

Two less dramatic options (which may conflict less...):

Bossk w/ VI, Gunner, Hotshot Copilot, and K4. Strip the tokens before Kath fires.

Or...

Drop Dengar crew for IG88 crew and pick up Iggy-B with PTL, HLC, AT, FCS, and title. Who cares if you miss if you can just straight out restart the attack? Plus, bonus HLC.

Asajj Ventress (48) - Lancer-class Pursuit Craft
Push The Limit (3), Latts Razzi (2), Glitterstim (2), Glitterstim (2), Gyroscopic Targeting (2)

https://geordanr.github.io/xwing/?f=Scum and Villainy&d=v4!c=48!218:27,61,202,194:44:19:&sn=Unnamed Squadron

https://geordanr.github.io/xwing/?f=Scum and Villainy&d=v4!c=48!173:220,126,34,21,121,215:-1:25:&sn=Unnamed Squadron

https://geordanr.github.io/xwing/?f=Scum and Villainy&d=v4!c=48!119:197,-1,24,139,143,202:22:16:U.28,U.28&sn=Unnamed Squadron

https://geordanr.github.io/xwing/?f=Scum and Villainy&d=v4!c=48!216:176,-1:43:-1:;216:176,-1:43:-1:&sn=Unnamed Squadron

https://geordanr.github.io/xwing/?f=Scum and Villainy&d=v4!c=48!123:37,-1,-1,-1:21:-1:;123:120,126,136,118:21:25:&sn=New Squadron

need more? just ask

Y-wings TLT (24), Y-wings TLT (24)

OR

Fenn Rau, title, PTL, AT (34), Z-95, BMST (13) and Inertial Dampners on Kath (1)

4 Headhunters, 4 headhunters is the answer xD

A 48 point Boba Fett is the traditional solution from that particular build...