How to avoid an Intranet hotchpotch - Part II

Last time, I asked how you can use a combination of fit-for-purpose technologies, while avoiding building an unwieldy intranet solution for your organisation.
If you already have 'too much knitting' and you're burdened with a hard to maintain mix of branding and code, then complex technical solutions such as deploying skin-swapping technologies like XDV may be an option. But this requires design effort to retrofit existing sites. Budgets get stretched and can leave you with even more of a maintenance headache.
In practice, organisations tend to learn these lessons the hard way. They build strategies to phase out or rebuild the divergent sites - but this time they fit all the components into a proper plan.
As in many things - prevention is much better than cure. Here are some tips we've picked up along the way when it comes to planning your technology mix:-
(1) Keep the user experience at the front of your thinking
For example, prioritise single sign-on. Staff who need different logins for intranet and e-learning tools can find this exasperating. It compromises take-up of your tools. Make sure your solution is barrier-free for users, and doesn't force them down virtual cul-de-sacs.
Your users should be entitled to simple, usable sites. If they're complaining of a clumsy user experience or having difficulties finding everyday tools they need to get their jobs done, the alarm bells should be sounding.
(2) Resist the temptation to adopt too many technologies - and go Open Source
Wherever possible, choose technical solutions that work easily together. OK - it's not always a good idea to build everything with just one technology; some tools are focussed on one particular job. For example, Open Atrium is great for deploying a Drupal based intranet. Moodle is unbeatable for e-learning.
You can't always achieve what you need with a single tool, but choose modular technologies that are flexible enough to react to future requirements nimbly and open enough to work well with one another.
(3) Get to know and trust your suppliers
I would say that, wouldn't I? But fostering supplier relationships that work in partnership with you can make all the difference. That way, it's in everyone's interests to build maintainable solutions that work in the long-run. And they you share your goals.
But what are your thoughts? Let me know what you've found works for you.