If we assume for a second that each player makes just as much profit after upkeep costs, as the next, then no clan should be at a disadvantage. So the fallen clan and all of its archers with low upkeep, won't be the only ones able to employ massive armies with the best equipment. "Playing more" isn't something that only benefits one clan, either. I've never seen a clan that only played on weekends. Roughly every clan averages the same weekly time played per player.
Ahem... you base all of the following on a terribly false assumption. Clans with a good part of cav (gk, legio, pecores, templars, bandits...) will have an hard time keeping their cav focus if everyone else makes even only 2x more gold in Strategus. People that play cav usually struggle to break even so I don't see how they could earn money without respec or retire and go inf or even better, archer.
Most of the active cRPG clans will want to set foot in Strategus. So cRPG will likely become a goldfarmingfest for those clans, as Strat will likely be very competitive. I want to play Strategus, but I don't want cRPG to become crap because of it.
Therefore, the upkeep dead zone seems a good idea. It's rather silly to have high level people intentionnaly gimping themselves and their team to gain more gold.
I think having very high (somewhat realistic) standing troops upkeep and low recruitment costs would encourage people to make many little wars. If you can keep your army doing nothing ad nauseam, then I doubt people will come up with many aggressive plans. If upkeeping armies is expensive, then people will likely use them as fast as they can, and have as little standing defense as possible.
Imagine two factions start the first war. They both have a good amount of stacked gold. They build armies and fight a little. Soon a fief of the second is conquered by the first and a peace agreement is signed. Now both have big, expensive and rather useless (they are at peace) armies. They have two choices : either decide they have enough cash to upkeep their army a little more and start a new war, maybe against another faction, or decide they are running low on gold, disband a part of the army and start making gold again. If big armies are expensive, then having a small army makes you earn money very fast. So you can very soon have enough gold to build an army and start another war.
Standing armies won't make the game feel medieval, nuff said.