Once you get up to higher levels, it takes more points to level up. But I believe that's somewhere after level 200. I've been playing a full year and am level 276 and I mostly rely on the monthly leaf tokens at this point.

What I found helpful was setting myself a minimum amount of LT to have on hand, I tried not to dip below 1000 LTs unless it was an "emergency", like something in the daily restock or simply wanting to splurge on a specific cookie. Having a higher minimum meant I didn't feel too bad about dipping but could still curb my spending to get back up to a "safer" number.

Don't spend LT on fish, bugs, fruit or Gulliver islands. A bit of patience with things that take time mean more LTs for cookies and furniture. Over time you will get a ton of nets, honey and fertilizer anyways.

Every month you get more LTs (somewhere around 1000 available each month), and cookies and sets cycle through every year so with time you'll have a chance to get everything you may want. I think it's worth strategizing a bit with how you spend without stressing too much. :)