ACROSS
 9. <report of wages> PAYSLIP = (PAS outside Y) LI P
10. <pagan> HEATHEN = H_ EAT HEN
11. <pioneer> INNOVATOR = INN + OVA + ←ROT←
12. <planet> VENUS = (.a)VEN US(u.)
13. <nail> TALON = T_ ALON[-e]
14. (CITRONS AS)* = CROISSANT <part of continental breakfast>
16. <Welsh region> CARMARTHENSHIRE = CAR MART (HAPPENS - APP) HIRE
18. <more suspicious> SKETCHIER = KETCH IE inside S_R
20. <following> AFTER = _A ER outside FT
22. <group of knights> ORDER = OR + ←RED←
24. →"BARRED HACKS"← = HARDBACKS <books>
26. <number> FIFTEEN = F IF TEE + _N
27. MONTAGUE - _U_ = MONTAGE <film sequence>

DOWN
 1. <given too much> SPOILT = SILT outside PO
 2. X + L <=< BY AND LARGE <in most cases>
 3. SLOVEN I_ A_ = SLOVENIA <state>
 4. S PAT = SPAT <argument>
 5. <hippodrome racer> CHARIOTEER = CHEER outside A RIOT
 6. CAVAS outside _N = CANVAS <tarp material>
 7. K + HAN = KHAN <ruler>
 8. <liqueur> ANISETTE = (IN TEA SEA)*
14. (FACING THIS)* = CATFISHING <pretending to be someone else>
15. CORSAIR* outside T + A T = ARISTOCRAT <duchess?>
16. CAS_ + TOFFS = CAST-OFFS <discarded clothing>
17. ←PALS← BANG = SLAP-BANG <precisely>
19. RM inside CAEN = CARMEN <Bizet opera>
21. <red-brown hue> RUSSET = ←(.i)TE'S SUR(f.)←
23. <challenge> DEFY = ←Y FED←
25. P after RUM = RUMP <cut of beef>