Okay so... this is not going to be a popular decision, but it's the decision I've made.
Both the Grenader and the Spearer will not be making the cut.
Considering only the end-user side of things, I would agree there is a lean towards accepting them - even if it's a much closer decision than the other two. However, there's a third factor that I've given weight to here, and that's the coding complexity. These skills have regularly been a source of bugs (keeping in mind that bugs prior to any release were a factor too, so the community would not be aware of every bug that's had to be dealt with), a lot of which arise from the fact that they're dependent on a second object, that at some times (but not others) must be kept "in sync" with the lemming (I will note that the Slider has also been a bit buggy at times, but a major difference is in the severity of these bugs - the thrower ones tend to be messy and complicated to fix, whereas most Slider bugs come down to "I overlooked something that, once I recognize needs to be done, is very easy to actually get done"). There's also a lot of edge cases that have to be considered around eg: terrain near the thrower, and the more I think about it, the more I realise there isn't really any "ideal" solution to these.
Ultimately - it's not any single one of the negative factors that lead to this, though, but rather the overall combination of them makes these skills, even if they do have a decent amount of potential, not worth the effort that would be needed to maintain them.
I will look to making a new exp build, with only the Slider and Laserer, and based on V12.11, sometime this week. At this point, given that the decisions have been made about which skills will make it and the physics are more or less finalized now, the next exp will no longer apply the "official styles only" restriction as I do not feel there is a significant risk of it being misused long-term anymore. I will stress that this does not mean that you can throw together a level in it and consider it "done and dusted" - there is still the possibility of physics changes that might require tweaks to the level, even if it's less likely at this point. It simply means that you can count on the skills themself sticking around, and therefore levels will almost certianly be feasible to migrate to a stable version.