Help a LOL player to choose some heroes to try

My personal goal is 15 at 3 minutes, rather than x at 10 / 15 / 20 minutes. This is because you should be adapting to the game's state. Just because you are a hard carry does not mean you should be farming until these points. You should be getting as much cs as possible when you can, but there are a lot of games that you and your team will benefit from you staying and fighting with your team, especially when you are a mid game carry like Lifestealer or Alchemist that can fight relatively early on.

However, very early on (like the 3 min I mentioned) you should ALWAYS be farming, hence that early goal.

Btw, 15 in 3 mins is around 75% of the creeps at that time, so it may be hard to maintain.

I hope it is ok to ask for recs here instead of making a new thread. I'm a new player too, been playing for a week.

So far I like death prophet(that ult lol), witch doctor(the q has a great sound effect haha), luna(this reminds me of the wc3 unit), axe(counter helix at early levels.....), sven(feels very tanky), venomancer(is there a limit to his wards? he's like dota teemo) and nature prophet(global teleport is so great). For lol, I absolutely love orianna(is there something like her in dota?), fiddlesticks, leona, tristana, I can't play the jumpy assassins like kha zix/le blanc/zed, I'm very very bad at those kind of heroes. What should I try next?

so, you like casters.you should try Zeus , Shadow Shaman, Lion.skillshot oriented(like orianna,you will love Earth Spirit,[Pheonix]]

Earth spirit is what I'm looking for. Thank you. :)