The latest updates missing some settings from app.css for wingpanel as well as from dconf. In what direction to go to change the panel since the screenshots?
sorry for my English
Feel free to visit this link for the first part of your question.
The easiest possible way of changing the date and time format is to type these two commands in your terminal:
gsettings set com.canonical.indicator.datetime time-format "custom"
gsettings set com.canonical.indicator.datetime custom-time-format "%A, %d %B %Y, %I:%M"
where:
%A - The full weekday name according to the current locale.
%d - The day of the month as a decimal number (range 01 to 31).
%B - The full month name according to the current locale.
%Y - The year as a decimal number including the century.
%I - The hour (12-hour clock) as a decimal number (range 1 to 12); single digits are preceded by a blank. (See also %I.) (TZ)
%M - The minute as a decimal number (range 00 to 59).
In your case, to display time only, you will probable need only %I and %M
Be sure to check this link for more detailed explanation of date and time symbols.
Update: Icon instead of text is not available for Loki anymore