I was about to say this, but I just had to read the whole thread before posting. Good thing I'm not the only one.

Imagine what would happen if the cheater accidentally used your MAC address...

On-topic: I'm having difficulties on choosing between option 1 and 3. Option 1 may be a bit too harsh, but then again Option 3 can be a bit too forgiving as well. (Voted Option 3 anyway)

I would like to see that if the cheater is found, perma-ban it right away. But depending on how they do the appeal (strictly via e-mail), we can then go for Option 3 for a month and keep logging their activity without touching the online scoreboard. They can enter online feature again after a month (or whatever duration as you wish) of restrictions. But if they found to be cheating again anytime (even after they're free from the restrictions), perma-ban without anymore mercy.

This method can be effective, only if we can find a way to prevent multi-accounts users. Unfortunately, I can't see any plausible method for this...

(I'm also hoping that peppy can find a way to detect Flashlight cheatings. Perhaps with some unique algorithms applied to the Flashlight mod)

aka. giving everyone the chance to try cheating once? sounds like an easy way for things to get out of control.

I think if any bannable offence happened only once in the past, a user should receive fair warning of consequences if they keep such behaviour (+ delete the record of score gained by foul play). If then they decide to continue, permament ban without possibility to appeal (or whatever you choose).

If said user cheated multiple times, instant perm should be applied.
An additional line mentioning this in the main menu could also be added.

i think osu! should have a antihacking system...... like other online games.....

Score reset, disable submission, but leave account access.
Also,

It does. The fact you don't know it's there means it's doing a good job; it should not interfere with normal users at all.

Score reset, depending on the intensity of cheating.

If it's a new account, made just for the heck of cheating, permanently ban it of course.
If it's a player who's been here for quite a while and cheats on 1 or a few maps, score reset him but keep his account.
If he'll cheat on like 10+ maps, then I'd suggest an account ban as well.

Ban Forever

just score reseting, don't ban them

Combination of Option 1 and 3.

Option 1 would be alone useless because every Derp can use proxy so he can continue to hack.
Option 3 would be the best way because it's theoretically the same as Option 1. But people will know that he hacked.
And not just because his name was ololololololololololololololo. About the combination:

Like GladiOol said:

It would be the best way after some Resets to ban.

In my opinion, if a player that was being here for quite a while decides to cheat, he/she/it should get the worst punishment possible.

Permanent BAN account, IP and MAC address.