UPDATE: The Ernie Ball Bass VI strings are successfully installed!
As per @Ritter667's brilliant advice, sliding ball ends from old bass sets overtop of the new strings got me past the small ball end issue. Although two minor issues did arise:
1. Taper length: I was worried about the taper not reaching the nut, but the exact opposite was true! The specification was 32.5, I measured a solid 33" which brought the tapers way past the tuning pegs on my E & A strings. I hesitate to cut the full thickness of the string in fear of the rounds unraveling, so I'm left with lots of excess string on a tiny peg. Not a huge issue with this set, but this would definitely render the DA EXL156 set mentioned in my OG post unusable, had I went with those instead.
2. Locking tuners: I'm probably the only one on this forum with a locking tuner equipped short scale bass, so this probably won't pose a problem for anyone else... But I intended to use the 90-74-54-30 strings: Bottom 3 installed no problem, but the 30 lacked enough beef for the locking tuner to grip well enough. Had to go with the 42 for a G instead. Ended up not being a problem, since I think a 30 for a short scale G might be pushing it. Bottom line, anything thinner than a 40 probably isn't usable for locking pegs.
Review:
Tone - Massive upgrade IMO. With shorties already being, in fact, quite punchy... The heavy sets it wore prior had a little too much oomph to it for my taste. I felt the lows always vastly overshadowed the highs. Since the change, I feel as though I'm now hearing the full tonal spectrum of the bass for the first time with the 90-42 set. It's proving much more versatile of an instrument than it was before.
Feel/Playability - Also a great improvement. I'm no stranger to thicker strings on a standard scale, but for my 30" scale I feel like anything beefier than 100-40 chokes out on the higher frets, especially this being a 24 fret bass. The string feel, response and tension of the 90-42 EBs on this short scale feel much more similar to a 45-105 on my long scales than the true 45-105 Sunbeams this bass wore prior.
Overall, I'm happy I tried these, especially for the cost! Although the excess taper length for the E & A mean I'll probably move on to other sets. Likely sooner than later as well, since we all know how long EB strings last... Will update as I go, and I appreciate you guys help!