Returning player looking for some advice/pointers

I see your wall of text and raise you another one.
Welcome! I'm kind of the opposite of you in that I've never started the single player and only ever played the multiplayer. And, I've been more than happy doing that. I'll try to answer most of your questions as best I can.

Yes, since you last played, a lot has changed but a lot has also stayed the same. I'm not sure about your specific connection issues. Hopefully someone else can help you with that. This game does have an annoying region lock though. If you are in a well-populated region, the US, for example, finding a game is not that hard. That being said, I mainly only search for perilous and nightmare difficulty games. I think threatening has a little larger of a player base but I have no idea in Routine. Don't expect to find heartbreaker games, not that I think you would be looking for them just yet. Also, some players play in private lobbies. You won't be able to find them unless they are on your origin friends list, which brings me to my next point. Try friending some people so you can join any games they might be in from origin. Check the google docs in this sign-up thread: bsn.boards.net/thread/454/damp-sign-bsn

ALSO in that thread, make sure you have the two expansions for the game downloaded. They are free (I think). If you don't, you will have a much harder time joining the game and will only have access to the small player base that also doesn't have the expansions downloaded.

Second, soloing is torturous to me. I hate doing it and the XP is terrible. Every harder difficulty gives more XP than the last. Something you may not realize is that the added XP for all teammates in a game is given to everyone in the game. So, playing with teammates speeds up the leveling and promotion process. A lot of this game is centered around good gear and promotions. Good gear isn't that hard to get. The best gear is hard to get. Promotions come with more time invested in higher difficulties. For now, your 2% heal-on-kill rings are probably your best bet. The Arcane Warrior is also one of the best classes for new players. Just equip your highest base damage staff so you can get the most barrier possible from any damage you inflict.

But, you should probably try to bring up your stats a little more evenly. Easiest warriors to stay alive with include the Lego, the Reaver (has health recovery on every hit). Easiest rogues include the silent sister and not sure what would come next since she is in a league of her own. Easiest mages include the Arcane Warrior, Saarebas, and possibly the Elementalist. The hardest to stay alive with in the beginning (in my opinion of course) is the Avvar, alchemist, and necromancer. But they all become fun a little later.

This is probably my most important advice. A lot of the damage in this game inflicted on you from enemies is physical damage (swords, arrows, etc.). Your armor plays a huge role in reducing this damage type. If you walk in with your stock base armor, it offers very little protection. You can craft better armor for any of your characters but it takes a lot of materials. If you can get 1,000,000 combined XP with any warriors, mages, or rogues, you unlock special drakescale armor (it's the very best armor in the game, also the ugliest...) for all characters of that class. 1 million XP sounds like a large number but remember, any teammates you play with add to this XP, any higher difficulty you play adds to it, etc. This armor, which will then be given to you in a free chest in the store, will make you almost invincible in routine, make threatening way easier, and give you a chance in perilous.

A good way to have a chance at decent weapons comes from dragon runs on the Ferelden Castle map. You (or someone else on your team) will need to craft dragon calls (don't use cotton!). You ring the gong on the third zone and then fight the dragon on the 5th zone. If you kill it, it has a chance at giving you a decent dragon weapon. I THINK (but would welcome verification from someone else) that you can get blue-rarity dragon weapons from threatening dragons and get the better purple unique versions afterwards from perilous dragons. Other than that, you have a chance at getting better weapons from any treasure room in the game or by buying chests in the store.

I don't think there is really a guide for when you can try the other difficulties. It depends on who you are playing with. Some people could solo perilous and nightmare making the game very easy. However, you will get bored if you are one-shot killed in NM and have to watch the rest of the game from the fade. With unlocking the drakescale armor, you should be able to do threatening and possibly join others for a chance at perilous. Nightmare is a big step up and the armor isn't good enough to keep you alive without decent promotions and gear without good teammates.

For your final question. This game is a grinder. You can't expect huge progress in a very short time period. However, I've always found it fun. You have to remember, all of us that are still here were at one time where you are now. I remember when I first started, watching a reaver destroy everyone while I was dead in the fade. And that's what I wanted to do so it inspired me to keep playing. Then, I would watch someone destroy nightmare on their own, and that's what I wanted to be able to do, etc... So you won't be able to tell if you want to commit to the grind without giving it a fair chance. The beginning is by far the hardest and most frustrating. But it gets way better a little afterwards once you start to get better gear, promotions, character builds, friends, etc. And remember, promotions and leveling up comes a lot faster as you get more promotions and can play in higher difficulties. Anyway, hope some of that helps.

Keep playing. The addiction grows with time ;-)

There is also an "enter proving grounds" option to test out builds with AI team mates.

I'm always impressed when I see this. I've played with some of the heavy hitters on this board in perilous PUGS, like Gekrakel, and they always play in a complimentary way to the rest of the team (when it would be easy for them to just steamroll everything). Makes it more fun for everyone.

In fact, Hunter and Terrell (and even Witty) were doing it for ME on Nightmare yesterday ;-)

Do you have the MP expansions installed?