Your G1 Architelone choices will affect the state of taxation in the Rim, but not yet in Irduin. The bit of the Rim Irduin borders on is still quiet enough that people think of it as a buffer zone against whatever the rebellion’s tax “policy” may be.
An untidy mix of both, I think–there’s not a real Ferme Generale. The Archons and aristarchs have the option to lease out their tax collection, a time-honored practice in many parts of the continent…but the vision behind the (still relatively new) Telone/Architelone system is to bring in outsider state agents to redress the weaknesses of the tax farming system and impose greater consistency in what is and isn’t taxed across the Hegemony.
In cases where the offices of Telone and Architelone continue to be granted by lease, the successful bidder often has a connection to the area being taxed, which helps them know and extract its wealth better than an outsider. But they’re also often clients of local magnates who turn a blind eye to their patron’s most profitable interests, while making up the difference by squeezing the other noble and merchant houses. This created enough unrest in enough cases that the Ennearchs started pushing the Archons to reduce their use of tax farmers and periodically bring in outside agents to discover and end corruption.
Local leaseholders are also more likely to earn their commissions by inventing arbitrary taxes that disrupt and strain the system of provincial trade that the Ennearchs try to maintain in Karagon’s favor. Ennearch Hypatia, who oversees that system (as well as the terms of the Hegemony’s much more limited official trade with foreigners), is also responsible for the state tax agent system, training Architelones and Telones to impose consistent taxes across the empire. Most Archons and aristarchs will sometimes draw on that system, and sometimes lease out the office, creating a patchwork.
ADAT @idonotlikeusernames pointed out the strategic location of Aveche and suggested it could “make a decent capital city for an eventual successor state,” which I’d not really thought of before that point – but he was absolutely right. @Winterhawk quickly followed up with the fever dream of the Great Aveche Canal, “That all the Seas may rejoice as one Ocean!” which will probably be the name of a final game achievement. 
I also first shared some details on the Unquiet Dead.