Well see the thing is you may only get ~1500 exp on miner now but it is fairly easy to just click on an item with a mouse or gamepad repeatedly and move from one point to the next. The Thing is its all based on percentages if you noticed that once you reach level 10 and start mining obsidian its only giving you like 80exp per obsidian outside of a chain. Then you hit level 11 you get 90 exp a hit the reason why is your exp bar went up in how much you need to level. That is the reason why it seems so uneven because you can easily make ~2500 exp in the same amount of time it takes to synth that 1 item. (exp is just a random guess and is being used as an example at this time) I do agree with you on the GP regen thing but the thing is later on is what they are trying to make you work for the level 50 mining items such as darksteel ore.