You may deserve more compensation, but it doesn't solve the problem in the long-term. As you have said, "There is little to no confidence in the others carrying on successfully if I suddenly stopped." Rendering that statement false is the solution. As the lead, it is your responsibility to improve the productivity of your team mates and build trust between them and the organization. It can be a slow process, but one that creates a more sustainable and harmonious situation for both you and your team. As long as you continue to absorb all the work, the situation will never improve.
Here are a few suggestions I've seen work in the past:
- Spend time on an extended vacation. This forces your team members to pick up the slack. It's better than quitting, giving everyone an opportunity to experience you being a single point of failure without the long term catastrophic consequences. Have a frank discussion about how to fix things upon your return.
- Offload yourself as a point of contact for various projects. Hand over initiatives to your fellow team mates. Force stakeholders to meet with them instead of you. Make yourself available to help them succeed.
- Make tasks more digestible for your team mates. Aggressively document things, make tickets easy to understand, set up knowledge sharing sessions.
- Hand new initiatives to your team mates. Let them specify the details.
- Talk to your manager, see if they have any thoughts on how to improve the situation. They are the last person who wants to deal with the fallout of your departure.
- Talk to your team mates, see what motivates them. What do they think they can do to improve the situation? It's not uncommon for team members to feel resentment for you absorbing all of the work.