Decent Team Comp for low level play (bronze and silver)?

I was thinking today, I do not do it very often so it was odd. My friends and I made a ranked team and intentionally hit Bronze V with it so we could do dumb stuff, normally we would just get a couple of us to feed so we could hit bronze and play things like ADC rumble or whatever we feel like doing (although we are only silvers). I was wondering about whether we would actually be able to climb out of Bronze if we tried and whether or not this team comp would work well.

TOP - Malphite - Amazing tank, builds into the combo well, people can struggle to build against him in lower level play. ALT TOP - Sion - Good tank, his ult is a fantastic stun and he can escape far better than Malphite in lane

JUNGLE - Gragas - A little bit more tankiness for the team, makes up for the lack of AP, gives our team some escape potential with good barell placement if things go sideways on an engage. ALT JUNGLE - Yeah I haven't a clue, Gragas is the only jungler I can think of that is a good AP/Tank with disengage and strong teamfight.

MID - Yasuo - Frequently banned, although less so recently because kindred and veigar being such huge problems ATM. Makes the combo absolutely brutal and is just a generally strong champion. ALT MID - Annie - Stun, strong in teamfights, but not having Yasuo on a team that loves to dive in would be a shame.

SUPPORT - Annie - Because of the physical damage in mid we also need some magic damage, Annie has butt loads of magic damage and brings an amazing stun to the teamfight. ALT SUPPORT - Nami - Nami combos with Yasuo, but she lacks the magic damage that annie brings to the table which gives the enemy the ability to just stack armour. If Nami avoids ulting for the combo she has a decent ability to help the team escape with her own ult if things go sideways.

ADC - Ashe - Brings yet another stun to the table and has a permaslow to chase down stragglers after the teamfight. ALT ADCS - Twitch or Miss Fortune - Each of their ults are really strong at killing a bunch of people at once.

• Varus - Gives the team longer to deal damage to the enemies after the initial combo rather than just letting them run away and chasing them down.

I am not really great at team comps and I know very little about league of legends, never really thought about them but I was wondering how well this would work. I DO NOT WANT some bullcrap about how "It is all about the player" etc... I mean, if the champion were played to a decent level with decent communication, how well would the team synergise and where are the big problems in the team?

Flaws I have thought about are

We are VERY team fight oriented (that is the point), other than Yasuo we do not really have the scariest lanes.

Our bot lane is not much, Ashe is a relatively weak champion and I do not know how will she synergises with Annie.

Please do remember that this team will not be used in a massively competitive or high skill level environment so I do not think that some factors will matter as much as others.