As I have been using slimefun a lot more in recent months, I have come across several things that should be adjusted, some due to some oversight when removing certain items, and others to improve the current experience.
Some smaller fixes include
Removal of the Crop Growth Accelerator (due to the Programmable Android Farmer no longer being craftable, it is not possible to create this item, making it pointless to keep in the menu)
Removal of the GPS Activation Devices (due to the removal of the Teleportation Matrix, these items are entirely useless)
Fixing the Zombie Pills item (they do not work at all, not sure why though)
And the more general fixes that I think would overall improve the use of slimefun include the following
Reduction of carbon crafting costs (it currently costs 8 coal to make one piece of carbon, making it incredibly expensive to create most of the useful slimefun items, with things like a single explosive pic requiring 4 stacks of coal to make a single one and the largest of fluffy barrels requiring over 24 THOUSAND STACKS of coal to make. Meaning almost no one can make them without either cleaning out the coal supply in their area or buying up a majority of the available market).
I would like to suggest the addition of the Slimefun ExtraTools plugin Github Link (which gives access to some additional items that may be very useful to the server overall. These include a Gold Transmuter, which would allow players to farm vanilla gold ingots without the use of large nether farms. Pulverizers, which make the conversion of cobblestone into sand much easier, and would hopefully decrease the need to destroy naturally spawning deserts. And a machine called a Concrete Factory, which allow players to easily convert concrete powder into normal concrete. Although I would recommend the removal of the Cobblestone Generator Machine given that it would allow for constant afk cobblestone collection.)
While none of these are necessary changes, I do think they would have a positive impact on the greater HM community. So I hope they will be taken into consideration.