To give u brief answers to ur questions....
1.)Almost everything has changed since hoto, with the exception that hos/dl/zs are still only once a day instances
2.) The game is now more then ever very cash shop dependent if you would like to run endgame instances. But if thats not ur goal and u want to be F2P only, then at the cap u can farm dod in dirty gear very easily.
3.) Since FA's departure with the game, the population is starting to come back around, but it took a major nose dive with chapter 4's release because of the Class balancing issues they decided to address.
4.) Well with the new zone, you could reach 50 with in a day or two depending on how much you like to quest. but the road from 50-62 is still pretty long considering you go from an enormous of xp per quest back to weeping coast where the lvl of xp per quest is significantly lower. Basically u go from 250k per quest reward to about 10-15k per quest reward. But once you reach 62 and get through limo, you could reach cap with in 4 days.
hope that helps.
