Hi Esteban, I tend to agree with your argument but...
about the current defaults, "enter" is the one that is choose for 99% of IDEs around the world (and yes, the 1% default is probably just Pharo 1.4).
All those IDEs offer both <tab> and <enter> to trigger code completion. If I enable <enter> in Pharo, the <tab> no longer works. I also wonder why I don't find the <enter> behavior annoying in other IDEs. Can it be the case that Smalltalk code has more 'line ends' that just terminate with a word? In many other languages, a code line is more often terminated with a non alphanumeric character (separators, braces, etc...). I am not sure about this but I wonder... In any case, is it difficult to enable the both <tab> and <enter>? cheers, Johan