Times Cryptic 27,948

[NeilMunro]

Very grateful for all help with these clues please.
1ac: “Depressingly little is invested in home improvements (8).”
2dn: “Potential killer of fish in strait and river (9).”
6dn: “Capital fellow on the Spanish Main? (7).”
16dn: “Flier uncovered book of navigational routes (7).”
24ac: “Cut juice to noisily swallow new socially-acceptable round (6).”

[Lie-in King]

1a Dismally - 'small' (little, in) 'DIY'
2d Strangler - 'angle' (fish, in) 'str(ait) + r(iver)'
6d Managua - 'man' + 'agua' (Sp. "water"; main; sea)
16d (p)Ortolan (book of routes, uncovered)
24a Unplug - 'gulp (noisily swallow) n(ew) u(pper-class)' (round; back)

[NeilMunro]

Many thanks again, Lie-in King!!