I suggest renaming the diffs like MM said (Breezin', Cruisin', Sweatin', Hard ROCK!).
I think you should not use use clap hitsounds in this map at all. Whistles and finishes sound much better and are enough.
[Extreme]
It's not extreme at all. It's moderately difficult [Hard], and it might even be a [Normal].
02:46:140 (7,8,1) - whoa, dude. That's too much of a jump.
02:06:931, 02:07:350 - add notes here.
02:13:535 (6) - 1/4 earlier.
02:32:091 (5) - ^
You have a lot of places where you should move a note 1/4 earlier. Look thru whole map (in 75/50%, if you need to) and fix them all, please.
02:56:834 (1) - nice, but it can be prettier. Look: http://osu.ppy.sh/ss/7496
To get it like that, use File -> Open .osu in Notepad and paste this at the very end of the file, in new line:
[Hardcore]
I understand it's EBA-style, but copypasting entire beatmap and just flipping it is not enough.
Apply the same mods as for [Extreme].
You really should remap it. La Roux - Quicksand is a great example of EBA map with very similar, but a little different Hard and Insane; look at it and get some inspiration.
[Standard]
00:43:271 (4) - 1/4 later.
01:58:123 (4,1) - spacing. I suggest to do it this way: http://osu.ppy.sh/ss/7497
02:01:898 (3,1) - spacing.
02:33:769 (2,3), 02:35:026 (1,2) - compare spacing.
02:55:784 (1) - 1/2 earlier.
[Entrance]
00:26:497 (2) - 1/2 earlier fits much better.
00:24:191 (1,2,3,4) - spacing.
02:46:557 (1,1,2,1,2,3,4) - spacing.
02:55:575 (5) - 1/2 earlier.
Overall, nice map. Keep going!
I think you should not use use clap hitsounds in this map at all. Whistles and finishes sound much better and are enough.
[Extreme]
It's not extreme at all. It's moderately difficult [Hard], and it might even be a [Normal].
02:46:140 (7,8,1) - whoa, dude. That's too much of a jump.
02:06:931, 02:07:350 - add notes here.
02:13:535 (6) - 1/4 earlier.
02:32:091 (5) - ^
You have a lot of places where you should move a note 1/4 earlier. Look thru whole map (in 75/50%, if you need to) and fix them all, please.
02:56:834 (1) - nice, but it can be prettier. Look: http://osu.ppy.sh/ss/7496
To get it like that, use File -> Open .osu in Notepad and paste this at the very end of the file, in new line:
88,176,176834,6,12,B|144:168|144:168|208:280|336:272|400:168|400:168|440:176|440:176|392:176|392:176|328:32|176:24|141:170|141:170,2,800,14|14|14
256,192,182075,12,4,185220
[Hardcore]
I understand it's EBA-style, but copypasting entire beatmap and just flipping it is not enough.
Apply the same mods as for [Extreme].
You really should remap it. La Roux - Quicksand is a great example of EBA map with very similar, but a little different Hard and Insane; look at it and get some inspiration.

[Standard]
00:43:271 (4) - 1/4 later.
01:58:123 (4,1) - spacing. I suggest to do it this way: http://osu.ppy.sh/ss/7497
02:01:898 (3,1) - spacing.
02:33:769 (2,3), 02:35:026 (1,2) - compare spacing.
02:55:784 (1) - 1/2 earlier.
[Entrance]
00:26:497 (2) - 1/2 earlier fits much better.
00:24:191 (1,2,3,4) - spacing.
02:46:557 (1,1,2,1,2,3,4) - spacing.
02:55:575 (5) - 1/2 earlier.
Overall, nice map. Keep going!