Ignore the crust. It's so thin compared to the rest of our planet, much less your planet, that it could be just as rich in metals as Earth and it won't matter a drop
But you will have problems.
Our core is liquid nickel-iron. That wonderful, giant ball of molten death does at least two things that could be compromised on a larger-than-Earth planet.
It creates our magnetosphere. Lowering the density means you're using something less dense than all that nickel-iron. Whatever it is, it won't generate a magnetosphere as well. That means more high-energy particles getting to the surface of the planet. That's going to cause lots of grief, like various kinds of radiation poisoning, heat damage, cats and dogs living together... mass hysteria.
It creates heat, which in turn warms the mantle, which in turn warms the planet. It's tough to stand in the middle of a Minnesota winter and think the planet core is helping any, but it does. Oh, it does. The sun would have a much harder time keeping our happy little jewel in space warm without it. You could compensate for this by moving the planet closer to the sun... but then there's issue #1.
And if that's not enough, there's one more issue:
- Gravity. Yes, you only want one Earth-G of gravity — you also want a bigger planet. Unfortunately, the funny thing about gravity... it causes things to collapse. And the lower the density, the easier it is to crush it into a higher density. In other words, the larger your one-Earth-G planet, the less likely it can exist according to the known rules of gravity. It would simply collapse to, fairly realistically, an Earth-sized globe. Something in the structure of the material that's lower density would need to keep the planet expanded to the diameter you want. But the lower the density, the less likely such a material is believable.
There are all kinds of theories about mega-earths floating around scientific and pseudo-scientific circles right now. They're educated guesses at best, speculation in the middle, and outright lies at worst. We've never seen a single habitable planet other than Earth, so there is no "scientific answer" to whether or not a mega-earth is realistic or plausible.
So, here's what you need to do...
Because we have no evidence that a planet larger than Earth can sustain life but some reasonably good reasons why it won't...
You need to ignore us and anybody who thinks you need to be "scientifically realistic" and build a great world. After all, our stated purpose (Help Center) is to be "a site for designers, writers, artists, gamers and enthusiasts to get help creating imaginary worlds." (Emphasis mine.)