So I was thinking they're should be interaction between the guilds like if you like just one guild and joined all of them u choose which side you're on and battle the other guild...

It would be nice, yeah. Daggerfall and Morrowind had some of this, but the later games are unfortunately without it. Instead you can easily become the overlord of all guilds with ease.

I think guilds with different functions shouldn't clash but I would like to have more warrior guilds or another rival thief or assassins guild (Morag tong is also in the lore)

But you're missing a vital component...WHY would we battle the other guilds...?
The only ones who MIGHT come into conflict are the Dark Brotherhood and the Thieves Guild.
The Companions generally keep to themselves, and the College is a center of education and is generally disinterested in anything that's not related to the arcane.

I'm sure they could write something up. Didn't the fighter's guild and the theives' guild in Morrowind conflict?

I think it would make more sense to be able to join rival factions to a guild (e.g. the silver hand, the penitus occulus), but we already have enough threads about that.

What? You didn't like fighting the silver hand?
Or the rivalry with the emperor's general forgot his name when you were an assassin?
What about the thalmor embassy quest?
Fact is there are rivalries I just want more

Given a proper reason, I'll concede, but in just this idea, I'm not really a fan if it. Just pointless factionalism, and we get enough of that in MMO's because god help us if there wasn't a reason to PVP.

All I'm saying is that you should be able to make your own guild,colors,guild armor,an HQ,and whichever one thieves,warriors,or assassins and YOU are the rival with the other one and the companions did have a rival clan or something,right?

Not really, as the Thieves Guild actually helps the Dark Brotherhood (at least, Delvin does).

The way the factions are written in Skyrim make it kind of idiotic for them to be fighting each other as they're all completely separate entities. There could be things like the Companions or College not letting you join them if you show up in thieves guild or dark brotherhood armor. And the other solution would just be make Vigilant/Occulus/Silver Hand/Morag Tong joinable. But alas, time constraints.

Ya thats good I love guilds and they kind of need to do more than that