First thing I noticed when looking to your team: your team have a lot of problems with Stealth Rock. Even with Hitmontop you still are really weak to it. And this problem takes to another one: you can't take physical hits quite well because Hitmontop isn't taking a lot of hits with no defensive investment while Arcanine will be wear down by Rocks(maybe this is why you can't deal with fightings).
This way, you will need to change a few things here. First thing is selecting another defensive pokemon in place of Arcanine, and maybe one of the best options is already in your team, but with a different moveset: Hitmontop
. As you alredy noted, Intimidate drops a lot the power of physsical sweepers, and with max Def investment Top can rach 317, while still keeping decent 256 Sdef without investment, while having a resistance to Rocks. Hitmontop and Umbreon will be able to take hits quite well together, since both have nice defenses and can kind of cover each other weakness.
Houndoom's best role is the same of Togekiss: a mixed set. This way, I think that Togekiss will be preferable for you, so instead of Houndoom you could run another special sweeper. I can see two options for you, Chandelure
. Chandelure can be prefered if you want to keep the fire immunity, since the ghost also have better immunities and don't need a lot of setup to hit hard, and with a Specs it can 2HKO most bulky waters with Energy Ball; Raikou, on the other hand, get rid of a Stealth Rock weakness, while being a good answer to both waters and grounds, as long as it carries Hidden Power Grass.
Now, with Arcanine gone, we have a free spot. Since your team aims for a Tokekiss sweep you need hazards, Stealth Rock specially. Now is where it get a little hard... Your defensive pokes, which are the best ones to set Rock, don't have it in their movesets; this way, the best thing I got in my mind now is running a suicide lead, and the best for your team, in my opinion, is Azelf
with Rock and dual screen. This way Azelf can make Togekiss life quite easier. With dual screens even a Raikou setup can be done quite easy.
In place of Flygon I would recommend Scarf Mienshao
, specially because it can hit harder and faster than the dragonfly.
So, this is what I can say about your team, many changes may not be the best one, but I hope I could at least show you some way to deal with some weakness of your team. Work Up Togekiss can destroy teams by itself, so I really wish best luck for you!