Tony. Give yourself credit where credit is due mate. First DSO stacking attempt without any photoshop adjustment.....Damn fine job.
Get yourself a cable or remote release Tony, you will be over the moon if that's the type of exposure you get with 30 sec. Stacking it really doesn't make it much brighter (without image enhancement in PS or such), it just increases the signal to noise ration. For brighter images before adjustment you need longer exposure time. And for that you need to use the bulb exposure.