so do I need to help aria with her rebellion or sell her to the slave market ?
and is it fun to play with kingpin trait ?
and I just found out that the cost to build workshop is much more expensive in the lastest version from 35k to 95k, just how am I supposed to find that much money lol. guess I'll play lots of poker in the dock.

You can only help Aria with the Rebellion (New World Order questline) or sell her to Kymanto Syndicate (Slave Masters of Raana). Currently the only two options if you wish to complete her quest chain.
Kingpin Trait is going to come down to personal preference on whether it's worth it, but from personal experience using it on a playthrough, I really don't like it. It really just opens up the Underworld early, which is nice if you want to roleplay siding with Bandits ASAP, but I find the loss in Influence each day and -25% Palace Accumulation Rating to be to much of a detriment and hindrance. In my opinion and experience, the cons don't outweigh the benefits. I will almost always pass on Lawful for the same reasons. These two traits are really just roleplay traits at the end of the day though, so it will always come down to personal preferences and how much you value the roleplay aspects even with the costs involved.
To get the money quickly you can-
Sell female Slaves you capture. If you aren't adverse to rerolling, you can F5 on the processing screen until they roll high Beauty/Charisma or high Value. I've seen values get up into the 30's. Girls like that selling for 10-20k+ right out the gate is possible. I have one that rolled with 130 Beauty and Workaholic Trait that's estimated sell price is something like 17k, but from testing she always sells for more than that; but I do have the Manhunter Trait. Outside of Workshops themselves and investments this is probably one the quickest ways to make money.
Take the loan out at the Bank if possible once you have the rest of the money in hand. Think this has always been a recommendation if you want to get the workshop ASAP. The Workshops usually pay for themselves pretty quickly, so you should be able to pay for the loan itself as long as you do something in game to make up the loss.
Do your medium/high difficulty Arena challenges, up to a certain point within reason; if possible. Some of them give a couple thousand I believe, but after a certain point they may be to difficult to do if you didn't hire the expensive mercenaries.
Gambling at Dockgrave is always an option when/if you have spare time with no groups of enemies to fight/capture.
I think these are the best ways to make money early game that aren't tied to the Workshop. Investments are a long-term thing and you need the immediate cash to build the workshop; and most everything else has bad rewards/time ratio barring doing bounties and getting good drops.