Across:
1 Most of (k) The Hill (‘peak’ without ‘k’ = PEA-) go to the local – head (local ‘head’ = -NUT) (PEANUT) barman probably provides more than one with a beer (PEANUT),
4 Medic’s business (PRACTICE) estimate (PR-ICE) covers what is witnessed in theatre (-ACT-) (PRACTICE),
9 Operatives lose vote (‘operatives’ lose ‘vote’ = perais = PRAISE) for tribute (PRAISE),
10 Spreads bits about (SCATTERS) models (= anagram indicator), stars, etc. (stars etc = SCATTERS),
12 Take time out (LIGHTEN UP) to go on a diet perhaps (LIGHTEN UP),
13 Sounds like (= homophone indicator) draft (‘draft’ = ‘draught’ = LAGER) that had to be pulled (LAGER),
14 Search thoroughly (COMB-) island (-I-) lands (-NATIONS) (COMBINATIONS) for a number of blends (COMBINATIONS),
18 Express an opinion (COMMENT-) on first sign of spring (-ARIES) (COMMENTARIES) with minute-by-minute reports on the game (COMMENTARIES),
21 Farewell (ADIEU) to colourful type (‘dye’ = ‘die’ = -DIE-) on the radio (= homophone indicator) in Australia (A-U) (ADIEU),
22 Free (= anagram indicator) Tunis hens (Tunis hens = NISSEN HUT) from prefabricated building (NISSEN HUT),
24 The foreign (LA-) support for the women (-BRA-) joining party (-DO-) registered (-R) (LABRADOR) in Canadian peninsula (LABRADOR Peninsula, Canada),
25 Key (music key = E-) to sad (= anagram indicator) dirge (dirge = -DGIER) (EDGIER) that’s more provocative (EDGIER),
26 Notices a (notices a) lark (= anagram indicator) (notices a = CANOEIST) paddling in the water (CANOEIST),
27 Temperature (T-) reflects (= reversal indicator) most of (y) Gary (most of ‘gary’ without ‘y’ = gar = -RAG-), Indiana – to begin with (‘Indiana’ to begin with =-I-), it’s cold (-C) (TRAGIC) and dreadful (TRAGIC).
Down:
1 Type of music (POP- music) at university (University of Limerick = -UL-) by outstanding (-ACE) (POPULACE) people (POPULACE),
2 A (A-) path (-WAY) from the estate (GAME) (AWAY GAME) leads to playground not associated with those at home (AWAY GAME),
3 Eurosceptic dismisses Cicero (‘Eurosceptic’ dismisses ‘Cicero’ = euspt= UPSET) as pushover? (push/knock over = UPSET),
5 Welcome (RECEPTION-) to sit (sit = -IST) out (= anagram indicator) (RECEPTIONIST) in the office to answer the phone (RECEPTIONIST),
6 Persian (CAT-) is briefly (e) isolated (‘alone’ without ‘e’ = -ALON-) on one (-I-) summit on archipelago (summit on ‘Archipelago’ = -A) (CATALONIA) in Spain (CATALONIA),
7 One (I-) finishing sentence (finishing ‘sentencE’ = -E-) in jail cell (cage = -C- AGE) (ICE AGE) in a major cold snap (ICE AGE),
8 Guard (ENSURE), engineer (E-), nurse (nurse), butcher? (= anagram indicator) (nurse = -NSURE) (ENSURE),
11 Off-key (INHARMONIOUS) in tune (-HARMONIOUS) after (= positional indicator) family members (kin) start off (k) (‘kin’ without ‘k’ = IN-) (INHARMONIOUS),
15 Safeguard (INOCULATE) from one (I-) getting to clean out (clean out = -NOCULATE) complex (= anagram indicator) (INOCULATE),
16 Illuminating (LIGHTING) celebrity (LIGHT-) in (-IN-) golf (-G) (LIGHTING),
17 Little known (ESOTERIC) mystic? (ESOTERIC),
19 Fishy type (GAR-) of starters with lobsters in ceviche (starters with ‘Lobsters In Ceviche’ = -LIC) (GARLIC) that leaves a pungent aroma on the breath (GARLIC),
20 A lot dropped by balloonist (‘a lot’ dropped by ‘balloonist’ = bonis = LISBON) on the Iberian Peninsula (LISBON),
23 Loses the head (w) with one of those carrying a torch (‘welder’ without ‘w’ = ELDER) for patriarch (ELDER).