If you have to use more towers to achieve base defense, you’ll have to abandon short base design.
The current advantages offered by short base did not appear until PG introduced flak towers. It has nothing to do with long base being bad. People pick short base design because that’s the best solution for the limited resources they have.
Now if ballista is required for rage drain, players will have to find an alternative to flak, twin mage, storm, ice design. A long rage drain island with just ballistas will not work.
I’m not proposing change just for the sake of change. Base design is too simple and too effective right now. It forces players to get over powered dragons to get 5 flames. It’s time to change the balance to favor strategy over raw power.