Is rank of 30426 in WBJEE sufficient getting a good engineering college in W.B. as a general category? If so, which stream is preferable?

Sorry to say but this rank isn't sufficient to get a good college through wbjee although this year's cutoffs aren't out yet if we look at previous year's stats the cutoffs of top colleges are high and even if you manage to get admission you might not be able to get the core branches so I would suggest you to wait for counseling but do prepare some backup option in order to be safe.
Good Luck!