Bitcoin has 3 use cases:
Store of value (digital gold)
You can contribute here by HODLing. Store most of your wealth in cold storage. This helps Bitcoin to become a valuable asset class of its own. You’ve got this down already.
Medium of exchange
You can contribute by running your node, accepting payment for your services on LN (or in BTC for large amounts), and then spending on things you need every month using LN (or BTC for large amounts). This would be a small portion of your total wealth ‘locked up’ (more aptly ‘freed up’) in channels. By using LN you support your savings:
- You will route people’s funds, which helps a lot of people especially in developing countries to be included in a global marketplace. Makes Bitcoin into a critically important global currency.
- Accepting and spending creates a vibrant economy around Bitcoin which helps with liquidity, stability and will increase bitcoin’s value.
- By using LN you contribute to lowering the on-chain fees which makes the base layer more accessible to more people.
- If you have considerable amount of BTC in your channels, you will earn routing fees. SATs that may worth little Today, but in 5-10 years they could be of considerable value. If you don’t constantly open and close channels you will earn more than opening fees, especially now that you can open channels with 1-2 SAT/vb.
- As you mentioned learning LN and everything around it (including the apps in the App Store) is already valuable Today and will be very important knowledge in the near future. You may be able to build a business around that knowledge or be hired because of it. It’s like learning about the web at the beginning and being able to create startups or be hired by startups. It could be life-changing for some.
DeFi / Trading
This is only for professionals and risk takers. I’m not knowledgeable to give advice on this.