Thanks for the suggestions!
At the moment, I do not plan on adjusting the intro page that results in additional complexity - while I could see this be useful for a smaller subset of users, I don't feel it's worth it at the moment to add that, even if it's hidden behind another setting that would toggle it from the current usage pattern.
As to the second one - we'd first need that data - "related words" is a very ambiguous term, and it would be difficult to start marking up terms like that without some terms easily having 10+ similar terms.
However, I do have a plan for this - it will not be as widespread as you are suggesting, but it's a good start. Once I have more vocabulary usage notes included that do comparisons between words, I will start to make it possible to view those both within the dictionary (in a different format from what is present now) as well as in other areas.
This year is going to see a HUGE amount (if things go well) of info added to vocabulary: categorical tags, more usage notes, related words, more opposites, formality levels, etc. A quick look at some words in the dictionary already shows a ton, and it's going to need a top-down redo of the layout so the data doesn't bury the most important information.
So I probably will not make any changes until I can look at everything that is being added, and figure out the best way to lay it all out.
When that times come, I'll definitely be soliciting community feedback, so I hope to hear more from you then!