Be careful in what you expect from pickups. They make more of a difference in guitar than bass, which isn't to say that they don't make any difference. Because basses are under greater tension, the materials and construction matter more, particularly when it comes to string feel and timbre. Classic Barts tend to be a little on the woolly side which is great for bright and rigid instruments, they will tame the highs a bit. They also tend to be a market leading shape but it's always good to to check as even EMG's and Barts can differ in width by a mm or two and that can make a difference to whether they'll fit or not.
I'm not familiar with the MK-1's in your bass but most of the Ibby basses I've tried have a prominent lower mid range and a slightly woolly upper end so replacement pickups might give you more to work with. But they won't make a good bass into a great bass.
Active EMG's are good for recording but they coarsen the attack a little if you're into hifi MM type crispness. You could maybe investigate their passive range though.
Many of the other soapbars (e.g. Nordstrand, Aguilar, Delano) tend to be pretty similar in sound and all of them are crisp and well balanced. You could also look at Seymour Duncan and Dimarzio but they tend to be for rock players if that's your thing. Q-tuners are super hifi and you can tweak them to manage where the resonant peak goes. Most manufacturers of flatter response pickups wind it below the threshold of human hearing.
Something else to note is that multicoil pickups are coming on to the market from multiple start ups like Turner. But they're not cheap due to the extra work in putting them together.