The Tri-Class options aren't good if you go for a full 6 man party. You level too slow and end up being a 'filler' character in the end.
You need a meat-shield. If you want to keep the Multi-Class flavor, you might need to use multi-player mode to create multiple PCs so you can have multi-classed meat-shields. (Fighter/CLerics work wonders in this area. They can become downright deadly when given Crom Faeyr, dual wielding, and Improved Haste
. Buff him up and set him loose )