Yes, I'm serious. By making towers weaker, sure, you make cavalry better - but you also improve non-cavalry units even more, relatively speaking, allowing you to do true rushes, not just raid. If towers had less attack, it'd be much easier to build rush strategies around units that currently get owned by towers, and thus are non-factors.
Nerfing towers would also be a boost to rushing strategies, and thus an indirect nerf to raiding and cavalry-oriented strategies. You'd still have crenellations, for anti-cav goodness, but other troops would no longer die quite as fast in the death star EZ-D-Fens starting area.
Weaker towers = More viable attack forms early
More viable attack forms early = Raiding is less dominant
Raiding is less dominant = RC are less of a no-brainer unit
Cheaper towers would make the game dull as heck, and would make even more players leave the game. Cheaper towers would mean that NO attacks would be possible in classical. They'd also mean that you'd be stalemating much longer into the game. You'd end raiding, of course, but you'd also end all other forms of serious fighting in classical and long into heroic. Shooting buildings are already too cheap/good. They're actually at the root of the entire problem. Because everyone starts with free towers (just buy an upgrade) they are hard to attack in classical. Arrow fire decimates any attempts at attacking the home base. Thus, the troops that do get used to attack are the ones that can stand up best to arrow fire - at least until crenellations is researched, which it rarely is. If the towers hadn't been there, it'd be much easier to attack with other units, such as archers or infantry early on. Cavalry would still have a theorethical mobility advantage, but in a situation where you have fast and powerful early rushes with infantry constantly threatening you at home, running out to raid with cavalry would be much more of an actual strategic choice.
Towers aren't the solution to cavalry, they're a part of the cause (the other part being that cavalry are too good, or too hard to counter) of the cavalry ascendance.