You are correct that SUM is a separate entity owned by the MLS. The MLS is itself an LLC, which owns all of the teams and gives its "members" (i.e. owners) a right to operate an MLS team. All players are employed, not by the teams, but the MLS, which creates its own issues.
With regard to SUM, I don't have too many issues with SUM negotiating this deal because US Soccer has contracted with SUM to go out and negotiate marketing deals on its behalf. SUM has the resources and skill set to do that and are experts in the vertical soccer market. Where I get concerned is when the marketing deal involves multiple entities as does the current TV Deal (MLS and US Soccer). I would much rather have US Soccer outsource its PR and marketing to agencies than do it inhouse at this stage because I firmly believe that whatever commission will be paid, the expert 3rd party will cover it a multiple of times over by securing better deals given its broader power in the market.
What we know is that US Soccer has not had a "presenting sponsor" willing to pay an 8 figure fee (somewhere between 10,000,000 and 99,999,999), so its found money as far as I'm concerned.
The general rule of thumb for a non-profit is to have at a minimum 6 months of reserves, up to 24 months of reserves. US Soccer's operating budget is roughly $125m, so its sitting on 12 months of liquid reserves ($130m). I personally believe that 24 months is about right, given the 2 to 4 year revenue cycle and significant costs associated with operating the Federation. US Soccer's income is not a straight line but a mountain range, with highs and lows. When the US National Teams do well, we get peaks, when they don't we get valleys, we also get valley when we have to invest in various competitions. 24 months of reserves is about right, so I wholeheartedly disagree with everybody that looks at that $100M as something that should be disbursed now. It would be negligent management for the federation to reduce the reserves, which is one of the reasons Cordiero was elected as President, he advocated for growing the reserves ...
but what does he know, he is just a Harvard educated international banker with more financial experience than everybody participating on this thread combined.
As to some of your other points, I would strongly encourage you (all) to go read the audited financials from last year. The SUM agreement is described and we know that the SUM marketing relationship has been good for about $25M annually.
https://www.ussoccer.com/about/federation-services/resource-center/financial-information
At the end of the day, US Soccer the role of the Federation is limited. It oversees and guides the Council members. Its fields the national team, but all the heavy lifting for youth is supposed to flow through AYSO, US Club, US Youth Soccer, which all have their own separate budgets. When youth players register to play soccer, only $1 of those registration fees flow up to US Soccer. I think $1 is ridiculously low, but it makes perfect sense when you consider that the role of US Soccer is limited and the heavy lifting is the obligation of AYSO, US Club and US Youth Soccer.