Two things from me:
1) Regarding the canvas replacement: Maybe I missed something but why should QGraphicsView not be suitable for the project? Implementing an own canvas on top of opengl or whatever is clearly not the main goal of the project and should be forwarded to some library

2) Regarding other software:
Today a friend of mine pointed me to this software:
http://fritzing.org/
It is a circuit design programm that has besides PCB and schematic view also a breadboard view. It is based on Qt4 and looks nice. They also have a working canvas.

Best regards

Axel


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Axel Jäger
Developer

basysKom GmbH
Robert-Bosch-Str. 7 | 64293 Darmstadt | Germany
Tel: +49 6151 3969-961 | Fax: -736
axel.jaeger@basyskom.de | www.basyskom.de