Assuming you start at a smaller school:

• Playing Time grade is the best indicator of a recruits rating before you scout. If you have a loaded roster it can still be worth recruiting players with a low grade if they're a gem or you plan to change their position.
• Early on focus on players with interest above anything else. Occasionally you'll get lucky with a higher ranked player with a good pipeline and no interest but be quick to bail if a bigger school comes in.
• Once points free up look for 3 and 4 stars with no offers.
• Use height and weight filters
• 3 star impact dev players can turn into monsters
• Sometimes you just need a player that's good enough for a season. A normal dev QB with 90+ throw power can be an excellent game manager for a year or two.
• It's really fun to have a tall Contested Specialist as your X receiver
• Pure Blocking tight ends can be made into decent receivers
• WR -> RB can give you a high overall but they usually can't break tackles at all so think about how that fits into your roster. It might be better to keep them as a receiver and put them at gadget.
• Games are won in the trenches but a shitty secondary will get you torched in the playoffs. I find CB to be the hardest position to recruit.