Your examples are cherry-picked, I presume through no fault of your own. You're looking at two medieval manuscripts and comparing them to two Roman inscriptions. This is a more typical example of a Roman Period manuscript. The scripts of the Roman world are quite complicated, but luckily there's no need for me to reinvent the wheel, since we've had a previous discussion. The major scripts we use today derive from the so-called Humanist Minuscule developed in the Renaissance. This script is not, however, descended especially strongly from the Roman capitals. Instead, the Italian humanists, discovering a wealth of manuscripts around the fourteenth century or so, incorrectly believed that the oldest manuscripts they had, mostly copies from the tenth to twelfth centuries, were genuine Roman manuscripts that had survived. They therefore modified the script they saw, producing what they believed was a "genuine" Roman script. In fact, these manuscripts were written in Carolingian Minuscule, which was developed from late uncial, half-uncial, the insular script, and some forms of Roman cursive, which still existed in parts of Italy.