Delightfully difficult
Across
1 Aim? To be so exclusive? ONE IN A MILLION I (one) in A M (a million)
10 I note woman importing fashionable source of dye INDAMINE
I N (note) IN (fashionable) in DAME (woman)
12 Utter wild words chasing USAF newbie ARRANT
AR (airman recruit) RANT (wild words)
13 Shrub branch divided by recurrent breeze BRIAR AIR< (breeze) in BR (branch)
14 Suggestions about distress bringing in outside pairs in competitions TWO-HORSE RACES
HORS (outside) in WOE (distress) in TRACES (suggestions)
18 Aloe vera not very active in sunken spots AREOLAE (ALOE [v]ERA)*
19 Manufacturer finally linked to some current craze RAMP
[manufacture]R AMP (some current)
21 Old apartment house yielding up second composite plant INULA
INSULA (old apartment house) minus S (second)
22 DNA material on the whole offering no recovery GENE
GENERALLY (on the whole) minus RALLY (recovery)
24 It afflicts firm during sudden increase SCOURGE
CO (firm) in SURGE (sudden increase)
28 Most of the grass – certainly venerable – beginning to threaten equine contest THREE-DAY EVENT
TH (most of the) REED (grass) AYE (certainly) VEN (venerable) T[hreaten]
30 Things I sieve for some ITEMS I TEMS (sieve)
31 Recalled ultimate in sense within pithy comments GNOMAE
[sens]E AMONG< (within recalled)
32 Completed line observed in company stuff OVERCLOY
OVER (completed) L (line) in COY (company)
33 Punches old drunk woman in Edinburgh gutters FOURPENNY ONES
FOU (drunk) PENNY (woman) in RONES (Scottish roof-gutters)
Down
1 Leading pair of athletes in double gold? One makes a speech ORATOR
AT[thletes] in OR OR (gold x 2)
2 Individual upset about right line in register ENROL
R (right) in ONE< (individual upset) L (line)
3 US state, I maintained, upset Ohio IDAHO
I HAD< (maintained upset) O (Ohio)
4 Thin material currently used in a rein’s construction NANOWIRE
NOW (currently) in (A REIN)*
5 Possibly first unidentified Lady Mass MISSA (RC) MISS A
6 Introduce, relinquishing power in exchange INTERLAY
INTERPLAY (exchange) minus P (power)
7 Story-teller half-twisted historic bit LIRA LIAR (story-teller) last half switched
8 Wintry sight – one in cold repeatedly entering island in Seine ICICLE
I (one) in CC (cold x 2) in ILE (French for island)
9 Shark: surfacing, flee ocean with one loose NURSE
RUN< (flee up) SEA (ocean) minus A (one)
11 Expressions of praise? Reviews critically holding water PAEANS
EA (water) in PANS (reviews critically)
15 Bird call descended steeply over the pond RINGDOVE
RING (call) DOVE (descended deeply US)
16 Responsiveness in the year during Georgian period REAGENCY
A (anno – in the year) in REGENCY (Georgian period)
17 Vessels stop turning up around customs house YACHTS
CH (customs house) in STAY< (stop up)
20 French actress increased acting with Universal MOREAU (Jeanne)
MORE (increased) A (acting) U (Universal)
23 Putrefies, giving off fluorine compounds ESTERS
[f]ESTERS (putrefies) minus F (fluorine)
24 It’s turned up furlongs and furlongs behind? STIFF &lit a racehorse that is a notably poor bet
ITS< FF (furlongs x 2)
25 Pollarded spruce attached by insects? EATEN NEATEN (spruce topped)
26 Volunteer brought in rings to show round shape OVOLO
VOL (volunteer) in OO (rings)
27 Expert in cycling world in France? DEMON
anagram of MONDE (French for world)
29 Frost upset Arab leader EMIR RIME< (frost upset)
( )* = anagram [ ] = omit < = reverse definitions in bold italics
Thanks Jed. Needed to come here for a couple of unches. Delightful as you say. Obeisance to the fiend!
Incidentally, you appear to have a typo when you transcribed the clue for 25dn – “attacked” not “attached”. Must admit I found that rather a woolly definition and wasn’t really convinced until I had most of the crossing letters.