If you bet an opening line there is also a chance the market goes in the other direction and you bought a worse line.
You said it yourself, you play smaller leagues, these lines don't come out many days in advance. Of course they come faster than for example NBA because most leagues only have 1 game per week (where for example NBA has like 3 games a week for each team) but not really several days in advance. The other thing about smaller leagues is that you can only bet a limited abound of $ there since many bookies have automated limits on these leagues, doesn't matter who the customer is.
If you want to take a look into it, search for RAS, right angle sports, they do free release shows often apart from their vip stuff. Open an account somewhere, brand new account without bet history on it. They only send ncaa men march madness, nba and nfl, only sides and total, no props/small shit, so only huge markets. And I can guarantee your account won't last more than 3 picks, betting on ncaa men or nba, maybe just maybe nba playoffs you can stick a few more than 3 picks.
Of course the market can go the other direction sometimes, he beat clv by 5.3% over many thousands verified picks = 2-3 picks and sayonara
Same as small markets football, they both last about as long but one of course has way higher than 5% clv.
I'm not originating any plays but I know where to find em.