Leash Excited/Aggresive

[newfie-mix]

Hi,

So I have a 4 yr old female Newfie-mix.
When we walk she is fine with smaller dogs, cyclists, runners, etc
She is mildly triggered by squirrels but I can handle that.
And she is good with bigger dogs that she knows (although she still often wants to pull to them to play)
But with new bigger dogs (usually medium and up) she is definitely leash aggressive.
And let's say 5 out of 10 times she will start a fight, and the other times it's an excited lunge to play.
But it's hard to tell the difference, and to know how the other dog is going to react.
What can I do to work on that?

A few things I've been told:
1) Distract them with treats the moment you reach a distance where they are triggered.
2) Use a C02 little gun thingy to distract them in the same way.
3) Also to start from further, and move in slowly until next to the dog.

Any comments, suggestions, ideas would be most welcome!

Thx