Just a few minor changes such as adding filler pieces between the tail segments to reduce gaps and replacing the canopies with the correct piece. Also created a new mini-sub that was intended to be a remake of the one that came with the Sea Wolf (6190 Shark's Crystal Cave), but it ended up becoming more of a whole new mini-sub rather than a remake. (The original had very few pieces, so it's kind of hard to remake something like that without totally changing it.)
I'm debating over whether or not to add the grabber arms as they do look a bit out of place when attached. I thought about trying to find a way to make them fold back underneath the sub so that they could be tucked out of sight when not being used, but so far I have yet to come up with a satisfactory method that accomplishes this.