Although I'm playing the DEI mod now( which is fantastic~) I am even more excited for this mod to be coming out as well and here's what I think would go well.
Politics system.
To make the politics system more interesting, I thought it would be better if each faction ideally had its own unique culture base. So if I was a Roman Governor, I'd be implementing reforms, or I'd be hoarding in all the cash to make maximum profit.( CA introduced these features, always the popping up events, love those tiny features) If I were a Parthian Governor I would be also building, expanding and generating wealth from the city I am in. For a barbarian tribe I'd rather have an event, more like the elders meeting around a place advising you to build what and what and will be the negative features of this and that. The random popup events which says a woman was killed and the murderers must be punished thing is an awesome feature. I'd love to see more of this featured in your mod.
The other thing is why don't you create a feature where you are just a governor or general that needs to gain power? If you look at Rome 1 you started off as a weak Roman faction that listened to the orders of the Senate, but as you grew more and more powerful you began to win support from the people and then boom civil war and you ended up being the most powerful man in the world. If this was done in Parthia for example, you start out as a local noble, and then you build and help your kingdom expand, but as your kingdom expands, people start to grow jealous of you as you win battles after battles, the King rewards with you money and treasures, there are numerous assassination attempts on you as you grow even more powerful. When your kingdom is under attack the King then sends you to deal with them and the story goes on from that. Still if these features were to be put in event boxes they'd make the game even more interesting. I would like a fully running Senate for Rome. Please check Grudge Nl's feedback thread( I'll link it soon). All the politics system really needs is a whole lot of features to be put in and the game is playable.
And please check DEI Silver Sheild Selecuid Pikeman. Man they look good, I'd rather you ask them to put them in your mod. Gerulla's 666 UI mod which is blood textures is also an awesome feature that would work great. Once you get TED, will you plan on remaking the cities to give it the full expansion it needed? And what about the siege of Carthage? Will you expand it and make it look like the pre alpha version? Its a real shame I can't play DEI and R21A together
Anyway, if there was anything else I'd implement the rome 1 faction videos into Rome 2. That would make the game a real feeling of the old rome 1 game. Still can't wait for your mod, good luck and may it work out successfully.
Oh yes and can you implement the Rome 1 campaign soundtracks with the Roman and Greek themes? That'd be awesome. Could you please implement Europa Barborum 1 and 2's barbarian soundtracks and menu soundtrack as well, and RTR's soundtracks? The barbarian soundtracks for Europa Barborum was also awesome, and I'd love to put it when playing as an barbarian faction instead of hearing the not so well made campaign soundtracks of Richard Beddow. I'd keep some of the Rome 2 battle soundtracks as they are simply put awesome. They work well with the game, check out Kittens Mittens channel on youtube.