I think the toffee pieces would work just fine - not sure about the rice krispies though. Here's the recipe I'm going to be trying this year for something a little different. It's from www.joyofbaking.com. I've also seen recipes for marbled bark that intrigues me but I can't seem to put my hand on the recipe right now.

White Chocolate Raspberry Brittle Recipe

Ingredients:

8 ounces (200 grams) white chocolate, coarsely chopped

2 tablespoons Raspberry Purée, at room temperature

Line a baking sheet with parchment paper and set aside.

Melt the white chocolate in a stainless steel bowl over a saucepan of hot water, making sure that the water does not touch the bottom of the pan. Stir until smooth. Watch carefully as white chocolate burns easily. Remove from heat, and using an offset spatula, spread the chocolate into a 10 inch (25 cm) square on the prepared baking sheet. With a spoon evenly drizzle the raspberry purée over the surface of the white chocolate. Using toothpick or bamboo skewer swirl the raspberry purée through the chocolate to get the desired design.

Let the chocolate brittle set at room temperature for 2 to 3 hours or until firm. Cut the brittle into the desired shape and size pieces and then peel the parchment paper off the brittle. The raspberry puree is slightly sticky, so handle carefully.

Store in the refrigerator in an airtight container for several days.

Adapted from Four-Star Desserts by Emily Luchetti

Here's a good recipe -

Diane's (Craftyrn)
Tiger Bark
===========
1 Cup milk chocolate chips
2 Cups (12 ounces) vanilla milk chips or almond bark
2 Cups peanut butter chips
1/2 Cup chopped peanuts
. Line jellyroll pan with foil. In microwave, melt 3 types of chips
separately, stirring until smooth. Pour melted peanut butter chips into
prepared pan, spreading level. Sprinkle on peanuts. Pour melted vanilla and
chocolate chips on top, drizzling each randomly. To marbleize, use knife to
pull through chocolate in wide curves. Refrigerate until set. Break into
squares .

A really good, quick, recipe can be made into bark or dropped by teaspoons. Melt white chocolate in a double boiler. Crush pretzels and add to white choloate. It's actually just like dipping whole pretzels into the chocolate but easier. Pour onto a buttered pan, I use jellyroll pan, and chill until firm and break into pieces. Or, as mentioned, drop by teaspoons onto waxed paper and chill.

This one is super easy and delicious.

DARK CHOCOLATE PISTACHIO BARK

Ingredients:

12 squares semisweet chocolate
1 cup pistachio nuts, shelled and toasted

Instructions:

Microwave the chocolate in a bowl on high for 2 minutes, stirring after 1 minute.
Stir until completely melted.
Stir the nuts into the chocolate.
Spoon the chocolate and nut mixture onto a baking sheet lined with waxed paper.
Refrigerate for 1 hour until firm.
Break into bite-size pieces.
Makes 1 pound---about 40 pieces.

I just wanted to do a follow up on the white chocolate raspberry brittle recipe. The raspberry is very sticky on the surface and the white chocolate is not setting. Arrrgh! I won't make this one again.

Here's one of my favs at Christmastime:

1# white chocolate (the stuff you buy at the grocery in big blocks. I think its called vanilla bark, or you can buy the white chocolate discs sold at Hobby stores).
1/2 cup toasted chopped slivered almonds
3/4 cup craisins (cherry flavored)

Melt chocolate in double boiler. Add toasted almonds and craisins and stir. Line cookie sheet with waxed paper and spread mixture over it. Put in freezer for about 15 minutes or until hard. Break into pieces. This is sooooo simple and good. The only negative is that 1 recipe doesn't make much, and its very addictive!