Domingo expressed his anticipation to BBC Radio Solent as skipper James Vince returns to the squad.
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"Somerset are defending champions, an established side, a well-balanced side, we have got a few bowling niggles we need to manage," Domingo said.
Lancashire captain Keaton Jennings aims to guide his squad past their previous knockout struggles. The team begins its season playing against Surrey in London on Friday.
"It's not often you start your T20 campaign down in the Big Smoke against Surrey so the boys are excited," Jennings said.
Nottinghamshire Outlaws seek to return to Finals Day for the first time in six years, opening their campaign against Yorkshire.
Outlaws bowler Olly Stone detailed the shifting focus of the squad to BBC East Midlands Today.
"The last couple of years probably haven't gone the way we'd have liked them to but I feel we've made some good steps in the right direction," Stone said.
Women's Tournament and Player Development
In the women's tournament, the focus turns to players missed by national selectors.
Warwickshire batter Davina Perrin is set to compete after being omitted from the England Women T20 World Cup squad by head coach Charlotte Edwards.
"Her time will come," Edwards said.
Sussex head coach Paul Farbrace highlighted the development of all-rounder James Coles, who was the most expensive men's player at the Hundred auction.
"He is one of the best talents in English cricket and has just improved year on year," Farbrace said.
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The men's opening round continues on Friday night with Middlesex hosting a match at Lord's, while Essex prepares for its first fixture scheduled for May 29.
