It is definitely your system that is causing Elements 3 to be slow. With my current computer configuration, I find that Elements 3 loads much faster than Elements 2. Switching from edit mode to album mode or vice versa takes less than 10 sec. My setup consists of Intel P4 3.0Ghz, 1Gb DDR2 ram, and a 128Mb ATI X600XT videocard. from what I have gather, 512Mb ram is the recommended minimum for photo editing and 1Gb Ram is recommended. A good video card and a fast hard disk helps also. A fast processor, while helpful is not that important.
Using PSCS with your current setup will be even slower. If you do not wish to buy a new computer, I suggest that you upgrade your ram to 1Gb, and change your video card to a more powerful version, like Nvidia5600 or ATI9600 and above. Also if your motherboard can support SATA drive, get a pair of SATA harddisks and run them in RAID array. Even if it is just 1 SATA harddisk, it'll run faster than an IDE harddisk.