Assume that they're both maxed out...
SA1: With one or two wulf shoots, you should be able to get hype very easily to get those evade stacks. This on command evade button is extremely handy since it can save your ass when you fuck up and/or safely intercept opponents to keep wailing on them. Also that 25% meter is a nice bonus.
SA2: With what was said about getting hype before, you should generally able to get this to proc with ease, so after 1 kill you're already in an even safer position along with a perma haste.
Snake is an extremely safe fighter, especially with that solid stack of evades and extra barrier padding. With him being a Beo, his moveset means you'll basically always be in control with the command grabs, with the SA2 possibly boosting your BB output and the extra safety of his SA1 during down time, which also gives you even more meter. I'm not sure if his MA synergizes with barrier, but if you don't sustain that much damage before getting a kill, the barrier and evade stacks will definitely secure Defending Champ. Also having the 3rd highest attack at 15,130 is pretty nice.
SA1: Think of the buffs as a small bonus but don't rely on them too much. Sometimes this can turn tides but definitely on that.
SA2: At a 33% proc rate, you should be able to expect 1 enrage per buff cycle, and combined with her attack, can absolutely snowball against opponents all the way up to the 500% modifiers with ease. Even 1 enrage on her is more than enough.
Djinn is an absolute ballbuster that blows Snake out of the water in terms of DPS. While she only has 461 more attack than Snake, she also has easy access to all those enrages, move stats that can boost her better, and a kit that pairs very well with her damage, such as with tricho nuking opponents in the air or just being able to combo heavily. With Leech, she has extremely high sustain thanks to all that damage she's dealing dishing out and healing from.