Yes, there are a lot of viable solutions on the table:
- Use a cheaper but just as secure chain - ETC? Litecoin?
- Delegates can optionally operate as payment gateways - the BTC fees are shared between various parties reducing the overall cost significantly.
- Increase the election interval.
- On hyperchains one might delegate stake to a delegate - staking pools might appear on the network.
- …
After we settle on a particular solution(or a mix) we will describe it extensively in the whitepaper.