League of Legends (LoL) Question: Is this comp as good as it sounds to me?

Blits isn't much to work on, if you had a nami instead, ori's shockwave can help her land a multi person bubble chained with her tidal wave, Akali would be ok but for the sake of having a wombo combo I'd replace her with rumble. everyone else seems fine.

The team you have made sounds like a weird pick/teamfight composition hybrid. The Blitzcrank doesn't really help with the teamfight comp that your team seems to be swaying towards. A much better pick in this case would definitely be a Nami, with pick potential like Blitzcrank, except with a very large teamfighting presence with Tidal Wave and Aqua Prison. Those are teamfight changing abilities.

There are many different types of compositions, and you should definitely cater to what you are aiming for.

The Teamfighting Comp: A composition with big AoE ultimates that are constantly looking to engage due to how good their teamfighting is. Does well against poke comps, but struggles against disengage comps and sometimes pick comps due to the fact that every man is generally crucial to ensuring the effectiveness of the wombo combo. An example of this composition would be Malphite, Orianna, Graves, Nami and Amumu.

The Poke/Siege Comp: A team with very long range and hard-hitting abilities that can whittle down an enemy when sieging down a lane, all the while not allowing the enemy to retaliate, be it through heals or simple range. The aim is to get structures and force enemies off them. Does well against splitpushing comps and generally well against disengage comps, but pick comps can tear them apart. Hard engage from a teamfighting comp may also cause some struggles. And example would be Nidalee, Nami, Caitlyn, Jayce and Kha'Zix.

The Pick Comp: Aims to catch out enemies that are out of place, which then allows them to capitalise on them being down a man to take objectives. All round a very solid comp for solo queue. While getting picks is good, the comp is too overly reliant on this. Their teamfighting is generally poor in an even situation. They can often snowball very easily due to the nature of the comp allowing them to get early kills. An example would be Blitzcrank, Warwick, Twisted Fate, Lucian and Akali.

The Disengage/Kite and Fight Comp: When the enemy engages, these guys aim to disengage and hopefully be able to catch someone out of position when doing so. Additionally, if people are chasing, these people aim to kite the enemies for as long as possible to deal extra damage. Does well against teamfighting comps, as well as compositions with a lot of immobile melees. However, the team generally can't initiate fights well, which leads to a more reactionary and opportunistic game to be played. An example would be Azir, Vayne, Janna, Elise and Gnar.

The Split Push Comp: Does not want to fight, but rather, uses map rotations to their advantage to outmaneuver the enemy in the map to siege multiple lanes. Often has one very strong duelist on the team coupled with a lot of very strong teamfight champions, or it could be a team of very fast pushers and duelists. A strong duelist is necessary as it forces more than one person to go deal with them, which then allows the rest of the team to go siege or engage when the enemy has lees people. An example would be Tryndamere, Nami, Lucian, Warwick, Orianna.

Early Game Comp: Often tied with another comp, these compositions aim to win the game early due to having such strong early game power. They often aim to ensure the enemy doesn't have a chance to get out of the early game, while the early game comp is able to snowball very early. Naturally, if they are unable to create a meaningful early game lead, then their lack of late game scaling will cause them to struggle. Usually pick comps and sometimes teamfighting comps. An example of this would be Lee Sin, Caitlyn, LeBlanc, Leona and Nidalee.

Late Game Comp: Often tied to another comp, the late game comps aim to survive through a poor early game to have an exceptionally strong late game. However, due to having a weak early game, they sometimes may not even be able to make it to late game. Usually teamfighting, splitpushing and disengage comps. An example of this would be Jinx, Janna, Orianna, Udyr and Jax.

Mid Game Comp: Often tied to another comp, the mid game comps are generally very solid throughout the game, but have an exceptional power spike after a few core items or when abilities are gained or maxed. This is when they should capitalise on getting objectives and fighting. While safe, they don't excel at anything in particular, and their window of time for when they are most strongest is often very small. An example of this would be Lucian, Thresh, Warwick, LeBlanc and Riven.

So you are aiming for basically an AoE CC/Damage fest. Why not use this team composition, then :
Malphitetop, Oriannamid, Graves/ VarusADC, Leona/ Vel'Koz or Zyrasupport and Jarvan IV/ Sejuani or Amumujungle ?

All these champions have both AoE CC and/or Damage, meaning they can either help set the combos up or easily fallow up.

And to answer your question. It's not a bad team composition, but it's probably not gonna work exactly how you imagine it.

I like the idea overall, but the problem is that a lot of it relies on poor positioning by the enemy team. If an opposing team has a blitz the carries should always be staying behind the creep, tanks, or stay out of rang. Yes the AOE is really good, and J4 Orianna is a very potent combo, but I would prefer other champs over Akali and Blitz. If you are going for AOE Malphite top goes really well with Jarvan and Orianna. I would also add a support adds AOE CC like Braum or Zyra. The comp isn't bad, especially the Orianna Graves and Jarvan part of it =)

if you could actually pull this off it would be cool but realistically, its not going to happen consistently enough for it to be a game winner. I would suggest going for a smaller scenario, for example I faced a cho/graves bot. Graves would blind then cho would rupture and it basically screwed anyone in it up. And the best part was that it didnt require a single ult. Basically because that was such a reliable combo it consistently turned fights in the other teams favor.