Take kinetics and speed boost your pet. 
Between Kinetics and Empathy I would say Kinetics. You will be welcomed for teams and you will be able to solo decently (still slowly tho).
On the other hand, Earth is a very strong crowd control set but quite weak for damage. That said I think you should consider a secondary set that could offer you even more control like Storm or Radiation.
@False Fiction - Virtue / Defiant
Current projects - [Glaciologist - Ill/Cold Troller] [Cloudshaper - Storm/Dark Def] [Harald Wartooth - Elec/Psi Domi]
I'm not a big fan of /emp for trollers unless you're building a PvP toon (i.e. an illupath). I've played earth/kin and it has good synergy. Otherwise I've teamed quite a bit with earth/storm or earth/TA trollers and both are good if you want extra control. Earth/rad is also an excellent combo.
CoX 50s: <ill/rad> <ice/ice> <fire/kin> <grav/sonic> <ice/storm> <earth/kin> <kin/elec> <cold/psy> <thugs/dark> <fire/dark> <dark/elec> <night widow> <EM/ninj> <mind/icy>
Earth/Storm ftw!
@Under Control
Earth / Rad would be my pick - its going to be my next choice to level again 
Im going to be making a stone troller and wondering whether to take kinetics or empathy as secondary. would 1 of them be more useful than the other if i have a stone troller or not? I just need a couple of answers and ill be able to make it