Should indie hackers build new innovative ideas or stick to a known solution?

I'd guess the risk depends on how lean you can run the project. If you can feasibly build something new that's low time commitment and low cost to maintain--especially if you can keep your day job--then you have more time to find product market fit. If it's a new solution but your target audience is already problem aware, it may be less risk than if you have to first convince them they have a problem to solve

The way we're thinking about it developing Gas Cents (an OCR and data driven gas log app) is that gas logs are a proven market so a) we know the problem is validated and b) we only need to convince a fraction of existing problem-aware people to turn our way--not win the whole market nor go out to find a new market

Just my random two cents. You can definitely succeed either way. Good luck!

How risky is it for an indie hacker to build a new solution to something?

Quite risky imo. Sadly I think this is the achilles heel of the bootstrapper: that risk is best supported by capital. And a lot of it.

This is because even if the brand-new innovative thing is legitimately valuable — and I assume yours is, @randallkanna! — the very fact of its newness means a lot of additional resources have to get thrown at it to make it work: user education, social proof, some kind of incentive to stop using the old familiar thing, etc. And these are on top of all the normal challenges of finding business traction.

Not to say it can't work! But it's good to have a healthy financial cushion beneath you when leaping into these kinds of adventures.

Strategy no dreamer would follow*: build something for known market (tactics 2), earning some money while researching "leap forward" ideas. Then allocate resources for the moonshot project, because this is high risk. Fund the experiments and implementation from the proven market venture.

*Because why to build "boring" products when you can chase the big dream right away :)

Well Randall, interesting question! For me, it's a matter of timing and taste.
Personally I suggest to start building known solutions. Then, when some experience and background you can choose to look for the innovative approach.

For ten years or so I always tried to create something new and be inventive. I created dozens of produces and none were really great, in hindsight. Almost none generated any revenue.

Recently I switched my strategy and applied a proven business model to a new market and this time it works wonderfully. Useful service, quick revenue, everything just makes sense.

Everyone's journey is different, so whatever works for you, but taking this middle ground (proven model for a new market) was perfect for me.

(No neee to check, it isn't in my profile yet.)