I'll be honest... I feel like a bit of a schmuck for not including a bikini top in the Bombshell pattern. I was working on one but it was not ready in time for my deadline and I thought in lieu of including a not-quite-up-to-snuff top, I would investigate some ways you could draft your own pattern.
As usual, Pattern School is a terrific resource for drafting custom pieces. They provide instructions for self-drafting a triangle, halter, bandeau and tie front bikini top here.
For a less laborious route, check out the instructions for this "endless options" bandeau.
This looks like an interesting variation on the bandeau from Martha Stewart (includes the pattern):
This is a cute bow front bandeau DIY:
For a vintage vibe, I like this Mrs. Depew "Beach Bra":
Burda has a few cute options. This vintage option reminds me of that Ursula Andress bikini from Dr. No:
I like this ruffled number but it would have to be modified to work with a stretch fabric:
Ohhh Lulu has some cute bra patterns that could work as a bikini. This Bambi bra is adorable:
I'm in love with the slightly gathered top of this free PDF pattern. It reminds me of the bust on the Bombshell.
This Norma Kamali top is simply a gathered piece of fabric attached to a strap that fastens in the back. You could use the halter pieces from View B of the bombshell and sew them to an interfaced band.
I have a bit of a 70's hangup. I'm not super into the traditional string bikini top but this one appeals to the Boogie Nights in me. It's basically two right angle triangles sewn together, with a channel sewn in at the bust to accommodate a string tie. The long pointy end of each triangle ends in another string to fasten it in the back.
Ed: Amy from Cloth Habit pointed out that this band is probably just sewn around a wide piece of swim elastic, not interfaced.
Lastly, you could adapt a bra pattern in your arsenal to work as a bikini top. I plan on using my bra block later this summer to make a very supportive underwire bikini top. This is undoubtedly the best option for my friends with larger ladies. Obviously you can't use a hook and eye closure since it will be visible, so you will need to modify your back band to accommodate a bikini closure.
A bikini clasp is sewn into both ends of the band and snaps together:
An S hook is another fastening option. You sew it onto one end of your band, and then sew a loop on the other for it to latch onto.
Have a great weekend everyone! Monday we will be back to work on the bust for View A.