Never said anything was wrong with house rules (I have a few lesser extent levels of my own). But some of these house rules mentioned do not make recruiting itself "harder", most actually make it easier.... House rules for recruiting essentially change how the CPU will play on the field.
What people are confusing in this thread is how to make the CPU challenge them in recruiting battles, not on the field games. If people use house rules to limit who they can recruit, i.e no oversigning, limit 5 star recruits, limit to pipelines, how does that make the CPU recruit "harder"? How does that make the CPU recruit smarter?
The affect people create isn't making recruiting itself harder, it's limiting how strong your team will be. It limits the quality of your roster... I.E. things that affect you on the field! Say you make a house rule of no 5 star players for backup positions. Does that make it any harder to recruit a 4 star player or lower? No, it doesn't. The affect it has will be on the field. You won't have a 5 star recruit on your team, and your ratings could be lowered.
Not a big deal for people who play every game... everyone can beat the CPU with all levels of talent.
But as far as oversigning... doesn't make recruiting harder. Cutting players and "diluting" the playing pool doesn't affect CPU recruiting, it affects the quality of what they put on the field.
All these house rules of who to sign, have no affect on who the CPU goes after, how many points they use, how often a top school gets their recruit, etc. The only thing house rules are affecting, is the overall ratings the CPU teams will have with their recruits.
Getting back to the original question posed in the thread... how do you make recruiting harder. You limit your points as a coach. Make house rules stating "won't put 700 points into a recruit", "won't give an early visit to lock the CPU out", "will only recruit what I need in recruiting battles and will not take a non-recruited player where I land them automatically", "will not fill my recruiting points up to level 27 where I max everything out". That's how you make recruiting harder.
Oversigning/cutting = Making the CPU stronger on the field. It has no affect on recruiting itself.
But in my original point about Phantom Restrictions... if someone wants to avoid house rules where they have to monitor their own behavior to meet their own personal criteria, the easiest way to do that is resetting a coach to level 1 in recruiting. Now you have the game limit you.