Captain Heath, one of a host of players sacked by the Zimbabwe authorities, took 5-72 to dent an early Sussex charge.
Mike Yardy (48) and Carl Hopkinson put on 87 for the second wicket but former Streak then accounted for the first four wickets as Sussex slipped to 138 for four.
Streak later returned to remove top-scorer Luke Wright for 54 and Dougie Brown took three wickets but Sussex hit back before the close to leave Warwickshire on 33 for one.
Nottinghamshire's title defence got off to a soggy start as the first day of their match against Yorkshire was washed out at Trent Bridge.
The weather also delayed the start for the second successive day at Old Trafford where both Lancashire and Hampshire were unable to assert control with the bat.
Lancashire took two quick wickets on the resumption and although Sean Ervine (44 not out) dominated a last-wicket stand of 41 with James Bruce, Hampshire were eventually finished off for 194.
Yet Hampshire were still in the game at the close, Ervine taking two wickets as Lancashire ended the day on 148 for six in reply.
Gordon Muchall was seven short of a double century as Durham began life in the First Division strongly against Kent at Canterbury.
Muchall was unbeaten on a career-best 193 as Durham reached 401 for five, the 23-year-old having hit 30 fours in 268 balls.
He put on 118 for the third wicket with Gary Pratt (52) and came together with Phil Mustard (67no) with the score on 233.
England opener Marcus Trescothick was still waiting to begin his season in anger after being frustrated by the rain in Somerset's Second Division encounter with Gloucestershire at Bristol.
Trescothick was unbeaten on nine when rain forced an early end to the second day's play with the visitors in trouble on 31 for two in reply to 437.
Earlier Alex Gidman hit 103, with Ian Harvey adding 45 on his Gloucestershire return Charl Willoughby was the pick of the bowlers with five for 125.
Travis Birt was dismissed one short of a century on his Derbyshire debut but the perennial strugglers still enjoyed an encouraging first day against division favourites Surrey at The Oval.
Derbyshire closed on 392 for six.
Debutant Lance Klusener and Bilal Shafayat both cracked centuries to put Northamptonshire in a strong position against Essex.
Former South Africa all-rounder Klusener hit 19 fours in his 133-ball 118 and put on 146 with Bilal Shafayat, who hit a rather more patient 118, to help Northants to 377 for eight.