Beginning Anew solution
by Kegler

The extra words’ first letters spell STARTING FROM SCRATCH; the seven modified entries each start with a different synonym for scratch.

Beginning Anew solution grid

Across
1DREADFUL (FAD LURED anag)
7PACT ("PACKED" hom)
11R + OAR [spinning]
12H + ITCH [Tom]
13EiSSEN (rev)
15ELA + STIN (rev) [athletes]
16AGE GROUPS (GOP ARGUES anag)
17SWATH (THAWS anag) [rye]
19F + LAP (PAL rev) [Tiny]
20ERRandS [immediately]
22MARB + LED
24DE(CREdit)ED
25[F/m]IRE [Nature]
27TIPS (rev) [gentle]
28DOZE + N
29CUTL + ASSES
33T(RINK)ET [field]
34RASTA (rev hidden)
35NEVIS (VINES anag) [rapidly]
36WHEn + T
37PSST (hidden) [often]
38NICKNAM + E (rev)
Down
1D + tRESSED (DESSERT rev)
2ROSE (SORE anag) [muscles]
3AREA (hidden) [Soccer]
4DINGH(I)ES
5F(REED + M)EN
6LIAR (rev) [Children's]
8ACTUALIZES (CUT AS ELIZA anag) [Razor]
9CHIPP(E)R
10TENSE (TEENS anag)
14SCARCIT(I)ES
18SAD + I + STICk [around]
19FREDERIK (IRKED REF anag) [the]
21RETU + RNS (TRUE anag)
23DENTATE ("EIGHT" hom)
26A + C(T)UP [chamomile]
30A + KINg
31SAWN (SWAN anag)
32I + TEM (MET rev) [headlong]