mob spawning

when ever i go to a new area or mine down in a cave mobs seem to be near non existent, even if its night time with maximum render distance and simulation distance i rarely can see more than a few mobs. most commonly i see a zombie or two, maybe a skeleton, and then rarely i see a creeper. i play on hard and even in the nether, mobs are few and far between. i have to constantly leave an area and return to get another handful of mobs. creating mob farms and places to collect their loot is near impossible. i am aware that similar bugs have been made. please i am progressed through the game to a point where i need to acquire large amounts of drops from mobs and am unable to do so simply becuase it seems mobs dont seem to spawn very well. of course the only exception is some spawners i have found they seem to spawn consistently every 20-30 seconds in groups of 3 or 4. i realize this may be something to be fixed over time but i would just like to say that mobs were one of the aspects of the game that always kept me interested and on my toes while playing. since i no longer have that worry of being attacked or having to defend myself on my adventures the minecraft game has lost much of its excitement and suspenseful gameplay. please remedy the spawning situation as soon as possible to reinstate minecraft back as the exciting adventure game it used to be. now its more like your always playing in creative or peaceful as mobs are not the problem or danger they used to be. just to make it a little more descriptive, i have a base in the middle of a savvanah biome and have a 30 block circle lit up wtih torches around me but no walls. i am able to afk there as long as i want without being killed even at night cause the mobs never seem to spawn.