Cryptic categories

Question

Below are four groups of cryptic clues. Within each group, the answers share a common characteristic. The four groups also share a common characteristic. Solving any one group should make it much easier to solve the others.

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Group A

1. Punctuation provides stylish mixup with new beginning
2. Insect in potato begets mechanical being
3. Arias of hobo's final death are confusing
4. Benefactor starts napping in entrance
5. Glorify and endlessly refine the final warrior

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Group B

1. Copy a note twice beside the ocean
2. Six repeated depot openings are intense
3. Curb bottomless citrus and miss the start of blockbuster
4. Symbol for a confused boxer without a place
5. Excavate that with a finger

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Group C

1. Obese friend with no head is deadly
2. Your mother, out of her sleepwear, gets embroiled on the first of November with an island nation
3. Let a heathen pass water once more without me
4. Miss, your mother is an obstruction
5. As inverted fuel for epic tales

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Group D

1. The sides on a heptagon where the shape begins to be level
2. Battle's debut is in folk dance with insurgent
3. Cadence is decided unconventionally without having eaten
4. Even fifty at party with no initiation
5. Recommend a joint without a clue, finally

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^{NOTE: This is the first time I've ever attempted to create cryptic clues. I appreciate any feedback, however minor, about what does or doesn't work, and/or any suggestions on how to improve the clues.}

Answer 1

Group A:

(COLO*)N
RO(B)OT
(O + LOSS)* = SOLOS
DO(N)OR
HONe + warriOR

Group B:

MI+MI+C (sea)
VI+VI+Depot
LIMe + hIT
(pugilist - put)* = SIGIL
DIG+IT

Group C:

FAT+pAL
pajama* - ma + n = JAPAN
P + AGAiN
MA+DAM
SA+GAS

Group D (thanks to f''!):

S+EVEN
RE(B)EL
determined* - dined = METER
L+rEVEL
REeFER

And of course, the common thread is that

they all have the same vowel in the second and fourth positions; which one it is is dependent on the group.