RA liveaboards cater to a wide audience. From backpackers to those who want valet service. Typically price will tell you what you are going to get. Fuel is a major part of the expense of running a liveaboard so the shorter the trip in both distance and time will factor in to the end price, but once you get out of the budget trips (which are usually shorter trips) mostly price determines level of "luxury" you will get on board. The diving is pretty much the same. More $ can get you more guides in the water as well, and guides in Indo make a difference. You will not want to be diving on your own like you would on a Caribbean liveaboard. You would miss too much stuff, particularly on your first trip. You just have no idea what to look for on your own and you would miss a lot of things that are hidden in plain sight.
My recommendation is look for a longer trip - in the 10 day range that goes to both south and north RA (Misool - south and the Dampier Straight - north). That will get you to most of the highlights of the area. Spending all the $ and time to get there and only doing a 7 day liveaboard is false economy IMHO. Land based in RA is great, but a liveaboard is better. The land based will get you to all the great sites close to where you are staying, a liveaboard has more range so you get the very best of the whole area. Stay away from the repositioning cruises - where the boat transitions from RA to Komodo for example. Once you leave the marine protected area of RA you will see way more dynamited reefs than you would ever want to.
I tend towards the higher end in terms of price because the difference between the mid range and the higher end compared to the total cost of the trip is pretty much irrelevant. However, I have travelled on a couple of the more mid range boats and both trips were excellent from a diving perspective. The food wasn't as good and the accommodations were more cramped. Made zero difference to my overall enjoyment of the trip.
My suggestion would be to pick a couple of trips that look interesting and come back with questions. Likely someone has been on that particular boat and will have answers.
First trip to Indo I would recommend spending some time in Bali, either before or after. I suggest at least a couple of days before to get over jet lag. Jumping onto a liveaboard after 30 plus hours of travel means you spend a couple of days recovering on a very expensive boat rather than a very inexpensive hotel room. (It looks like you might be coming from Hawaii so this may not be needed - not sure what the routing and timing options are from there.)
I did my first few trips booking everything myself and it worked out well. I now book through a local travel company Underwater Tribe - its just easier. One of the owners was the cruise director on one of the trips I did. The two owners live in Indo and really really know the area so can create a custom itinerary for you that meets your needs pretty quickly and are in country if something goes wrong. I have found that using them takes a lot of the stress out of travel in an unfamiliar place. Their people meet you when you arrive and make sure that you get to where you need to be when you need to be there.
To get to RA from North America you are probably best to travel to Jakarta and then on to Sorong. I always leave a day between international flights and domestic flights within Indonesia. You do not want to schedule tight connections here. I have only needed the extra time once, but I really needed it as without the cushion I would not have made my flight home. Two other options are to fly into Bali or Monado, but there are way more options out of Jakarta. The only reason to fly into Bali is if you want to spend some time there (which I almost always do). The reason to use Monado is if you plan to dive Lembeh - or because it is a shorter flight to Sorong and the connections to get there work for the airline you are using (Singapore Air).
