How does running index funds with 0% expense ratios differ from running diversified 401(k) funds?

Gusto payroll data can be synced with Guideline, which offers various 401(k) and IRA plans.

Are there All Weather or Golden Butterfly index funds?

Which well known index funds are weighted and which aren't? (This is probably not common knowledge, and might be useful for your pitch)

Given that you can't buy fractional shares, how and when are weighted indexes rebalanced to maintain the initial weight?

Like most funds, the S&P 500 index demonstrates Survivorship bias: underperformers are removed from the index, which thus is not a good indicator of total market performance over time.

From https://www.investopedia.com/articles/investing/030916/buffe... :

> Buffett's ultimately successful contention was that, including fees, costs and expenses, an S&P 500 index fund would outperform a hand-picked portfolio of hedge funds over 10 years. The bet pit two basic investing philosophies against each other: passive and active investing.

It's common for (cryptoasset) backtesting to have the S&P 500 as a benchmark. Weighted by market cap, the S&P 500 may or may not have higher returns than cryptoassets (for which there were not ETFs for so long).

Do you offer index fund backtesting; or, which performance and relative cost savings metrics do you track for each index fund?

How would a hypothetical index fund have performed during stress events, corrections, drawdowns, flash crashes, stress testing scenarios, and recessions; according to backtesting?

Do you offer fundamentals data?

Do you offer [GRI] sustainability report data to support portfolio/fund design?

Do you offer funds or index fund design with an emphasis on sustainability and responsible investing?

Can I generate an index fund to focus on one or more Sustainable Development Goals?

What is the difference between creating an index fund with you as compared with holding stocks in a portfolio and periodically rebalancing and reassessing?

IIUC in terms of cryptoassets:

- A (weighted and rebalanced) index fund is a collection of tokens.

- Each constituent stock or ETF could or may already be tokenized as a cryptoasset.

- A token is a string identifier for an asset. A token is a smart contract that has the necessary methods (satisfies the smart contract functional interface) to be exchanged over a cryptoasset network with cryptographic assurances.

- A "wrapped token" is wrapped to be listed on a different network. So, for example, if someone wanted to sell NASDAQ:AAPL on a different exchange or cryptoasset network they would need to wrap it and commit to an approved, on-file ETF fund management commitment that specifies how quickly they intend to buy or sell to keep the wrapped asset price close to the original asset's before-after-hours-trading market price.

- (ETFs typically have low to no fees. When you own an ETF you do not own voting shares; with ETFs, the fund owns the voting shares and votes on behalf of the ETF holders).

There are EIP and ERC standard specifications for bundles of assets; a token composed of multiple other tokens. A wallet may contain various types of fungible and non-fungible tokens. For wallet recovery and inheritance and estate planning, there's SSS, multisig transactions, multiple signature smart contracts, and Shamir backup, and banks can now legally hold cryptoassets for clients.