Kastie has written two novels in hard cover (Simon & Schuster) and three in soft, and this is the equalizer. Not only that, but this mammoth valentine to suburbia, middle class marriage and the clash of generations has a lot of showmanship which should produce results in either binding. It is polished pulp. The leading character is Matt Swain, a free spirit and a builder who has a long on-again, off-again romance with Addy. Around these two, and against an upper Westchester development, swirl Steve Rand, an occasional philanderer whose teenage son is a delinquent; Dave Lerner trying desperately to raise his Brookiys family out of their Jewish heritage; and Joe Bialdi, frantic to give his daughter the advantages he never had. The hopes and harassments, family troubles, sexual conflicts and money worries of these assorted characters come across in a plot as closely constructed as Levittown, and in dialogue full of folks-next-door- nuances. Definitely a woman's book, and the Evan Hunter market seems the most likely.