I guess I've read something different in the OP's question than it seems what most of you have. . .
From what I understand he/she is asking about the idea of using and MDMA experience to "reward" him or herself for accomplishing his/her weight loss goals. . .
I didn't read that they wanted to use it to help treat their depression or change their mental outlook on anything. . . (although I realize I may be completely wrong)
So in answer to what I THINK was the OP's real question. . . I don't think this is a bad idea at all. . . You've given yourself something to work towards. Something you enjoy. I think people do this all the time whether it's buying a new wardrobe or going on a special trip or whatever. . . in your case you've just decided that your treat will be an MDMA experience. IMHO there's nothing at all wrong with this type of motivation. (well with this substance at least I suppose I may rethink my stance if we where talking about something physically addictive or that you where dependent on)
Now I see two other things in your post. . . first you ask about how we experience our rolls and enjoy them. This varies for me widely. I've done it in all sorts of settings and circumstances. It's ok if you're not into clubs or EDM. While i've enjoyed it that way it's certainly not the only way you can enjoy it. It's really pretty unique to each individual person how they might best enjoy a certain experience. For me personally my favorite setting is with my significant other at home by ourselves but I've also had lots of fun in nature settings (springs, woods, parks, beach etc) with friends both at night and during the day. I've had fun at theme parks and water parks. You really can have fun just about anywhere doing just about anything. For me it's always been more about who your with than what your doing for the most part. That being said I've also done it by myself and enjoyed it (though i tend to want to be with someone for the most part).
Let me say something here. . . IF you plan on going somewhere either by yourself or with someone make sure you plan it in such a way that YOU"RE NOT DRIVING while under the influence of this or any drug. It's just plain stupid.
As to the last thing in your post I'd like to comment on . . . You mention that your current path is steering you away from substance use. I don't know exactly what your path looks like and it's a very personal thing and ultimately your choice (and yours alone) I would mention that OCCASIONAL and RESPONSIBLE substance use and a healthy, mature, and balanced life don't have to be mutually exclusive. You can have the best of both worlds. You just must make sure the emphasis is on occasional and responsible use.
I've posted my 3 rules before but I'll do it again. IMHO living by these three simple rules can help you maintain balance, health, and happiness in your life while still enjoying substances.
1. Before considering to use all responsibilities must be taken care of. This means nothing put off, no upcoming deadlines, no upcoming obligations. Kids/tasks/responsibilities are taken care of and do not require attention. (if you have kids they're at the grandparents for an extended period of time) Basically there is nothing in your life that you need to attend to for a while and you're not putting anything off to enjoy this substance.
2. Any money you will spend on the substance must not be needed for something else. This is a pretty big deal. This means you're not in crippling debt. You don't have bills due that this money should go toward. You're not going without something you need in order to get the money for the substance. Essentially the money you will spend on drugs is entirely extra that you don't need for any other purpose.
3. Usages should be at a maximum of once a quarter and preferably every 6 months. Give yourself plenty of time to recuperate between usages and PLENTY of time for the experience itself. A 3-day weekend is perfect for me. Rule #1 must be true throughout this entire period. I give myself the first day for the experience. The second to simply recover and enjoy the afterglow. and the third to clean up and return to normal. Real life isn't re-introduced until day 4. . . so for me 3 full days with real life resuming on day 4. I do not want any lingering effects when my normal responsibilities resume.
I've found by living by those 3 simple rules I can maintain a balanced and healthy life and yet still enjoy some of the substances I've come to love. I hope this helps and hopefully I answered your questions! Keep us posted!