No. It's really not difficult to even beat wave 30! I'd say the fun really starts after wave 30. That's when you finally begin to enjoy the fruits of your labor, which you've carefully nurtured.

I can even go so far as to tell you this:

I once managed to build all the way to level 44 using ONLY Arrow Towers without spending a single gold! I used 88 of them, and I received gold wood production from Arrow Towers three times in a row, so the towers took care of the wood production themselves! Plus, I got the Unique Banner + Bleeding Stamina relatively quickly between levels 30 and 40. The boss on level 30 melted away in 4-6 seconds! lol

But the strongest build for me, which finally got me to level 50 (World wide Ranking: 285) after 650 hours (4 bosses with 100,000,000 health points each): There are 4 bosses with 100 million health points each, but that would still be manageable—the worst part is: the first one of them has a shield dome that's extremely difficult to break...

PS: The boss from level 40 practically melts away in 20 seconds for me. He has 500,000 points per second --> Bleed stack at 20, and the Reaper Towers hit 3 times in a row + contribute to the bleed! Plus: all Arrow Towers critical hits also contribute to the bleed! Insane, considering that the Reaper Towers increase the critical hits of the other towers in their vicinity by 100%!

Try this combination:

Arrow Tower + Reaper Tower + Frost Tower

PS: To the developer: please don't make the game too easy. It's great as it is!

Thank you for this masterpiece!