Namely, we cannot use tab to indent the first line of a paragraph. The key has no effect. 
      We also cannot enter multiple spaces before the beginning of a line, since the forum will eat them. 
We have an indent function, but it cannot be effectively used to indent just the first line of something - it either takes the entire paragraph with it, ends up taking along anywhere from half a line to several due to the different resolutions of screens (and window sizes), or breaks altogether. 

As a person who can be rather particular when it comes to the aesthetics of text (and this is a roleplaying forum, so we see a lot of text!), I request either permitting multiple spaces (or tab-sign), or alternatively actually having a separate bit of QQCode added which has a similar effect, and just creates a four or six spaces long blank. 
As it is, we cannot even color text to insert a bunch of "invisible" markings before each paragraph (yes, I have gone so far as inserting [color=#000000]_ _ _[/color] in the beginning of each  paragraph on other forums). And I honestly find the disjointed look double-entering after each paragraph creates both ugly to look at and very hard to concentrate on reading (it ... somehow takes me the effort to correctly identify the beginning of the next paragraph after each such empty line).