cursor-type controls how the appearance of the cursor, defaulting to
t, which uses the cursor specified for the frame (see the docstring for options). If you'd like the cursor to default to a block, you can
(setq cursor-type 'box).
evil provides a number of different cursors for the different states, which you can adjust to give you a visual reminder of what state you're in when you're typing:
The docstring states that each of these:
May be a cursor type as per
cursor-type, a color string as passed
set-cursor-color, a zero-argument function for changing the
cursor, or a list of the above.
So, for example, if you wanted a yellow bar 5 pixels wide in insert state and a purple-filled box in normal state, you could do the following:
(setq evil-insert-state-cursor '((bar . 5) "yellow")
evil-normal-state-cursor '(box "purple"))
See the docstring for
cursor-type for your options in adjusting the cursor.