Wonderful 7k Cryptic / Acrostic
Becky, BlueJay, Malrog

Attempt to solve these seven cryptic clues:

- Famous multi-level marketing attributed to bloke, reportedly from London, building the biggest burial structure in the world (5,7,2,4)

- Old arboretum suspended assorted dangers of young student working (7,7,2,7)

- God-like figure united splitting nation by waterway to the east - a plot I may upset (6,2,4,2,7)

- Steam Fair people met partying in the Southern US place to worship Diana (6,2,7,2,7)

- Overground tomb worried slim morale? Chant "USA, USA, USA!" (9,2,13)

- Nautical warning: "Brighten home!", with old communication around edges of lake and narrow inlet (10,2,10)

- Sculpt ornamental stone primarily used for schools' statue (8,2,6)

Having solved some (or all) of the clues, try to fit every unique word from the answers into the spaces in the grid below. Each unique word must be used only once.
The highlighted column should reveal a thematic phrase