if you really want to patch up this issue with scarf latias, just replace jirachi with the standard cb scizor. scarfrachi breaks the momentum of the game, while cb scizor adds more pressure to your offense. u-turn is the real bread and butter of the set, as it forces switch-outs, racking up U-turn damage (even resisted) and you can bring in your next pokemon to scare the opponent's away. simply put, scizor is the defensive backbone on many teams and i'm quite surprised your not using it. scarf latias will get OHKOed by Pursuit, but you would need to load up special defense investment to actually resist draco meteor better. go for 160 HP / 176 Atk / 24 Spe / 148 SpDef for your EVs to take gengar and latias' assaults much better. this way, you can pursuit locked in latias, removing it from existence the entire match. 176 atk + cb will still hit hard, i just think the added bulk is more needed to check latias.
on suicune, you could go for a bulkier approach to check gyarados and salamence once scizor is gone. go for 252 hp / 252 def / 6 spa to cushion gyarados and salamence's hits better. keep the same moveslot. the absent of stealth rock on this offensive team is not good. i suggest replacing machamp right now. azelf is your standard lead, and you could try it out to taunt sleep leads, set up stealth rock, and go out with a bang with a bone shattering explosion. this starts a quick momentum in the match, helping your sweepers in the long run. lastly, you could really try all the speed you need. starting off with salamence, go for 252 spe to take advantage of the naive nature. on breloom, go for jolly to outpace tyranitar. gl.