The quest for technologies with superior device characteristics has showcased Carbon-Nanotube Field-Effect Transistors (CNFET) into limelight. In this work we present physical design techniques to improve the yield of CNFET circuits in the presence of Carbon Nanotube (CNT) imperfections. Various layout schemes are studied for enhancing the yield of CNFET standard cell library. With the help of existing ASIC design flow, we perform system-level benchmarking of CNFET circuits and compare them to CMOS circuits at various technology nodes. With CNFET technology, we observe maximum performance gains for circuits with gate-dominated delays. Averaged across various benchmarks at 16 nm, we report 8x improvement in Energy-Delay-Product (EDP) with CNFET circuits when compared to CMOS counterpart. We also study the performance of a complete OpenRISC processor, where we see 1.5x improvement in EDP over CMOS at 16 nm technology node. Voltage scaling enabled by CNFETs can be explored in the future for further performance benefits.