Bo has great contact skills to there's no concern with his k rates, but I have a hard time thinking that he wouldn't be well served to develop a little better plate discipline. He's constantly behind 0-2 due to his extremely aggressive tendencies, and despite a good two strike approach he would be far better off if he were able to lay off of more bad pitches and him himself in more hitters counts. It's a true testament that he's able to still produce a 118 WRC+ despite being in the top 10 in swinging at pitches off the plate, but I'd love to see what he could do with any kind of improvement in selectivity. I really think the key for him to fully unlock his potential at the plate is going to be forcing pitchers to give him more pitches on the plate that he can do damage with. I'd rather see him have hit his ceiling which is more like MVP caliber player rather than being capped at 4 or 5 win player he likely will continue to be if he continues hacking away.
I looked up Gurriel's plate discipline numbers for the first two months of the season vs from June 1 and onward, and he's made a dramatic improvement in swinging at pitches off of the plate. He's improved from swinging at 41% of pitches off the plate earlier on to a more manageable 34% during his hot streak. During this period he's basically doubled with WRC+ for the later period compared to earlier, as the first two months his WRC+ was only 78, vs 143 for June 1 and onward. That's a rather powerful suggestion of how much it can improve a players outcomes at the plate when they stop swinging at everything that comes their way.