Yes, I agree your Pardosa is in the agrestis group, and monticola on very old or unimproved grassland is a good possibility. It will not be mature at this time of year, but this is a difficult group even with adults under a microscope and good lighting!
Pardosa palustris is the only member of this group which is straightforward to identify (as an adult under a microscope). There is a lot of variation in epigynes and palps and reliance only on the figures of these is fraught with danger, and misidentification is not unusual. Locket & Millidge British Spiders is an essential aid. Voucher specimens of adults are absolutely essential for this group and anything at all unusual, improbable or unusual habitat etc should be checked by an experienced arachnologist. Even the most experienced arachnologist can have difficulties with some specimens.