Is there any reason why a person would pick a Fighter Plane that's worth 1275 over the EMP system that's worth 1300? The EMP simply outclass the Fight Plane in virtually every way.
The flash strike is way too powerful for a 150 point scorestreak. Good thing scorestreaks don't stack in this game because people will be spamming the strike.
Also, there's little reason to use the explosives dogs because the K9 unit can do mostly the same job. Sure, the dogs explode but it will too situational.
The low ones would be too easy to get and cause massive spamming since they would be earned every 5-10 seconds.
The High ones
#1 is too OP people would complain
#2 Doesn't make sense since most of the time the other team wouldn't have any air support to begin with if you got it.
It's a good thought to have even lower scorestreaks for the players who are having trouble obtaining any sort of streak. However, if they're lower than the already low UAV streak, they need to be balanced. A way to do this would be to create streaks that don't benefit the entire team, but possibly benefit a single player (either yourself or a teammate) or deter a single enemy player.
I would not object to the following:
Single Person UAV: 200 points
-UAV would reveal enemy locations to only one player on your team, or reveal one enemy to the entire team - 30 seconds - no assist score awarded
Single person CUAV: 250 points
-CUAV would block enemy minimap to one enemy player, or prevent the entire enemy team from seeing one player on your team - 30 seconds - no assist score awarded
...something along these lines.
This would allow a less-skilled player to be slightly more stealthy, or have a slight advantage over the enemy, while not providing any additinal points via assists.
I would also suggest that these two streaks could be shot down just like a normal UAV/CUAV would.