In my opinion i think you should get the Coal Bag and SoE for a few different reasons. The Coal Bag is never a bad choice especially in f2p. F2pers superheat a fair amount to make some gp and exerience. If you are looking for a really good guide that shows the xp/hr and how many ores to use and what not i suggest looking up "Water's f2p superheating guide" on youtube. Remember, this is pre-EOC but it will still help you with a few different things. Now the SoE is just good becase you can save GP which is always nice. :)